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How do I batch replace video clips in Premiere to graded copies? (from Da Vinci Resolve)
My color grader and I are working in parallel.  I'm editing in Adobe Premiere, and he is grading in Da Vinci Resolve (version CC 2015.2 and 12, respectively).  I gave him an early rough cut of the film to start grading.
A lot has changed in the cutting of the film since I exported him the rough cut XML of the project. The typical round-trip workflow I find online is to export XML projects back and forth between the NLE and Resolve, but that doesn't work for us because the Premiere project has changed so much and will continue to change.
Instead, we're trying to have Resolve render graded replacement video files for all of the source clips used, and tell Premiere to point to a different source clip.  The following technique seems to work, but has to be done clip by clip: "Project Pane > Right click > Replace Footage".
Is there an easier way to do this transition in Premiere and Da Vinci Resolve?  Or a better workflow in general for a colorist to work in parallel with an editor?

Method 1
First, with the Premiere project closed, move the original files that you're editing with to a new folder or other location. Open your project and it will warn you of missing files. Click the Relink others automatically checkbox and then hit Locate.

Navigate to the folder with the new graded footage, find the first clip and press Ok. It will then re-link all the other files to the matching files in new folder.
Note that this will only work if the files have the same name. Different extensions are ok, from my experience it's smart enough to deal with it if your original footage was an MXF and you're replacing it with an AVI for example.
Method 2
In your project window, or in your timeline, select all the files you want to replace, right-click and choose Make Offline. Generally you want to choose "leave the media files on disk" in the dialogue that opens, because it permanently deletes the file if you don't.
Once your clips are offline then you can re-link. With all the files still selected, right-click and choose "Link Media". This will open up the same dialogue as method 1, so as before you choose Relink others automatically and navigate to your graded footage.
Again, this only works if the graded clips are named the same as the originals.
Method 3
With the project closed, move the original clips from where they are on your hard drive, and replace them with the graded clips. When you open the project it will link to the new clips, again, provided that they are named the same. You will need to re-render any rendered clips in your timeline.
Another note is that if your footage contained audio you need the graded footage to contain audio, even if you're not using it. Premiere won't accept them otherwise. So in Resolve, make sure you check the "Render Audio" box.
I use this workflow when I'm working with BlackMagic Cinema Camera footage. DaVinci Resolve gives me much better results than the Adobe grading tools, either in Premiere or Speedgrade. The only thing that does nearly as good a job is using Adobe Camera Raw by opening the footage in After Effects and rendering out intermediates, but that is extremely tedious and dog-slow.

I use a similar workflow, also with BM footage and Resolve. I start by using Premiere's "project manager" to copy all the used clips (and only the used clips) to a different directory for grading. Then, in Premiere, right-click on the header row above the bin area, select "Metadata display," and add the "video usage" column. Sort by that, and then you know which files you've corrected (and you can delete the others from your project if you want, since they're not used anywhere).


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Adobe premiere, how do i link two audio clips and one video clip for the purposes of the razor tool?

So this is what it looks like. I have one video track, three audio tracks. The last audio track is background music. I need to edit the clips to cut out the boring parts. The problem is, I want to kind of be able to hear the background music as I play the video in preview. Anyway So normally what I do is, I press shift, and it allows me to use the razor tool to cut all clips at the same time, then i select and drag things into place. The reason why I can't do that here is, the shift razor tool will cut the background music too. What I need to do is link v1 a1 a2 for the purposes of the razor tool so that i may edit them as if they were one clip, how do I do that? I tried link, but link is grayed out for some reason when I select more than two things. Thank you!

What about locking the music track (the padlock on the left of the track number)?

Even though Michael Tiemanns answer is technically correct, it seems overly complicated given the description of your problem, as nested sequences may cause other problems and inconveniences down the road. So here are two other options that might help you:
Grouping
Select the three tracks you want to edit, then right-click → group (or press CTRL + G). The grouped clips will all be selected when you click on one of them. Then you can press CTRL + K to cut all clips in the group at the position of your playhead. The problem with this method is that the cut clips will still be grouped together, so if you select one of them, they will all be selected and moved simultaneously. The next option will be more convenient for your workflow:
Track locks
Click on the lock symbol on the left side of the timeline on the track that holds your background music. This will completely lock all clips on the track, preventing you from accidentally cutting or moving them.

You can make V1 + A1 + A2 into a nested sequence by selecting those three tracks and then right clicking to reveal Nest or by using the menu item Clip > Nest.  Then you can use the razor tool on the nested sequence without using shift.  Chop and rearrange to your heart's delight.

it didn't work. I selected v1 a1 a2, went clip->nest, used the razor tool on one of the three layers, and only one layer was cut. https://i.gyazo.com/45f1fed771ddaa5055f5641827c85f7c.png

I forgot how schizophrenic is Premiere Pro when it comes to audio.  MortizLost gives a better answer, including one I would have suggested next: the Track Lock.  I think it may also be possible to link clips (as opposed to merely grouping them), but again, Premiere Pro's incoherent design might again foil that idea because it tries overly hard to apply special-case logic to cases that could be seen as general solutions.

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


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Select some pixels from imported movie to duplicate and stretch
In Photoshop if you want to stretch some part of an image you can use the marquee tool to select the pixels you want, use Ctrl+J to duplicate and then Ctrl+T to stretch it.
I have a video recorded using a mobile phone in the vertical position and I want to do the same thing to repeat the sides of the video (it's a person talking and there's a painted wall behind him). Is it possible?

It is possible, but it might look a bit weird.  Video is constantly changing - even just a video of a wall will have noise in it, so static images tend to look a bit odd in comparison.  But Ii you stretch one pixel of the noisy moving image, you'll get lines of noise moving either side of your image, which might not look great either.
However, if you want to give it a go, duplicate your original image, use a mask to only show the edge that you want to extend, then adjust the scale in one dimension only (you'll need to click on the little link icon to only adjust the x-axis scale).
Alternatively, What many people do for a backdrop is to copy the image, scale it up to fill the screen, then blur, and darken it, and place it behind the original image.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


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Join 2 videos to play at the same time
Let's say that I have a file1.avi and a file2.avi. Each one of these files is the same size, for instance 300x100.
How could I join them, so that both of them would play the first 10 seconds of each video at the same time, one on top of the other, in a 300x200 video?

Use
ffmpeg -i file1.avi -i file2.avi -filter_complex "[0][1]vstack" -t 10 joined.avi

This will stack the videos vertically and play the first 10 seconds of each. Remove the -t option if the videos are longer and you wish to extend the output. This command also uses the default parameters to encode the video i.e. codec will be MPEG4 Part 2 (Xvid..). If there's any audio, the track from the first video will be used and encoded as MP3.


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LED light types
I'm trying to shoot video of a buddy playing music. I have a room that I need to light up for the camera. I'm looking into LEDs as they have good light output/low heat.
What is the difference between a NEEWER CN-216 with 13W total power / NEEWER CN-160 w/9.6W max power
VERSUS
Buying a clamp light and throwing a flood LED light in it, such as Hyperikon PAR38 14W (CRI 90+)?
Total is around $22.50 per LED+clamp vs a CN-216 which is $40 with lower wattage. Besides portability is there anything else I'm missing here?

One thing you're missing is colour. Cheap LEDs have all sorts of nasty spikes in their spectrum, so they often give off light that looks white to the naked eye, but will give skin a sickly greenish or magenta-ish cast. The on camera light you suggest will probably be all over the place as far as colour goes, but it will likely be in the ball park compared to a domestic bulb. Buy a cold shoe adaptor with a 1/4" thread, and then work out a way of attaching that to some sort of clamp.

@stib I thought this article was interesting: http://www.popularmechanics.com/technology/gadgets/reviews/g164/incandescent-vs-compact-fluorescent-vs-led-ultimate-light-bulb-test/  -- looks like LEDs in general have better color reproduction than CFLs (according to their test). LEDs look to be second only to incandescent bulbs and of course sun light :)

Thanks for that link. That article focussed on the perceived quality of the light, which is less relevant for shooting video, what was useful was the spectral distribution of the light - as you can see incandescent light has a very smooth spectrum, so it's very easy to balance. LED is smoother than CFL except for a bulge in the yellow and a spike in the blue. The problem about that is that the camera will pick it up much more strongly than the eye, resulting in colour shifts - it's especially noticeable on skin. The smoother the spectrum the easier to grade it is.

The first question you asked answers itself: just read the specifications of the two products and compare.
The second question you asked is perhaps more interesting.  LED matrix lights on cameras give to video the kind of look that flashes mounted on cameras give to photographs.  They separate foreground from background due to the (typically) large falloff of light between nearby and distant objects.  They tend to create a very contrasty look, with surfaces perpendicular to the camera reflecting lots more light than surfaces less so.  I.e., foreheads and cheekbones will be very bright, sides of face less so.  Being relatively small sources, they tend to throw distinct shadows, but because of their location relative to the camera, the camera doesn't see the shadows.  The LED matrix lights can obviously be removed from the camera and placed on a stand, but you haven't mentioned buying a stand or a shoe mount, and you might hate the shadows that they do cast, so they are likely to wind up on the camera.
A clamp light can be mounted off the camera, and a clamp light needs AC voltage, so you have to find a place to plug it in.  Since LEDs burn as cool as they do, it's easy to put diffusion across the face of a clamp light.  Large-faced clamp lights can give you even softer light, which means fewer distinct shadows falling on your subject.
If you do go with the PAR lights, you might want to get a second one so that you can use one for a key light and one for a fill light.  Or get a third so you can add a rim light.  Three point lighting makes all the difference in how things look in video.
If you go the PAR route, I recommend looking at SORRA Vivid (CRI 95+) products.


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Add black (or other color) padding when doing vstack (or hstack)
I am using the following filter_complex to put 2 videos of resolution 320 x 240, one right next to the other:
-filter_complex "[v1][v2]hstack=inputs=2[videoout]"

This works great, but now I was wondering how could I do it, so that I could add a small padding between them. Let's say for instance 5 black pixels (even though I would love to be able to customize the color or at least the distance).
How could I do that?

First, setup a color filter of the same height, and then add it to the hstack
-filter_complex "color=black:5x240[c];[v1][c][v2]hstack=inputs=3:shortest=1[videoout]"

See the options for the color filter here.

Alternate method is
-filter_complex "[0]pad=iw+5:ih:color=black[0v];[0v][v2]hstack[videoout]"

I added this filter, and now my video grows endlessly. Before I had a 20 second video, and now I had to interrupt the process, because it grew without limit...

Now I get a "Option 'shortest' not found"

shortest=1 works here. Recheck for typos..etc.

It does not... ffmpeg version? Mine is 2.8.6

You need a build from Dec 2015 or later. Use alt method instead.

The 2nd option "pad" seems to work alright, but just makes the padding on the bottom or the right. How would it be, if I wanted to pad the top or the left side? Or all at the same time?

The syntax of pad is W:H:x:y:color, where W and H set the size of the new canvas, and x,y defines where the original video is placed in the canvas, measured from the top-left. Default for x,y is 0. So, pad=iw+10:ih+12:4:7 creates a canvas 10 pixels wider and 12 pixels taller than the input and leaves padding of 4 pixels on the left, 6 on the right, 7 on the top and 5 on the bottom. Default color is black.

There is a way to achieve this result that may be more relevant to your interests:
Problem: Resize videos centering them in the middle of a pre-determined rectangle, letterboxing if needed.
Answer: https://superuser.com/questions/547296/resizing-videos-with-ffmpeg-avconv-to-fit-into-static-sized-player
The key line from the answer:
ffmpeg -i input -vf "scale=1280:720:force_original_aspect_ratio=decrease,pad=1280:720:(ow-iw)/2:(oh-ih)/2" output

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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positioning Trapcode Particular Obscuration Layer correctly
Using Trapcode Particular, I'm trying to position an obscuration layer so that half of my particles (spherical emitter) are being seen, then I rotate it around and see the other side of the sphere of particles.  But, I can't seem to position  the emitter and the obscuration layer correctly with respect to my other 3d layers (AE classic 3d). I can see all elements in wireframe mode except the emitter and obscuration layer. Any tips or tricks?

To see in wireframe objects, which is parts of effects (like emitter), just put in the scene Null Object and parent your effect point (emitter, etc) to it. After that, to adjust your point, adjust Null Object position.
Null Objects are visible in wireframe.

That's a great idea, thanks.  But, since the 3d position of the emitter is broken down into two parameters in particular, would you write an expression to follow the Position XY, and another expression to follow the Position Z?

I don't exactly remember, how it was done in Trapcode Particular... But you can try it like this.


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Splitting and regrouping stereo's right and left channels (Stereo to Mono)
I have several (rather old) videos of which probably due to an encoding error by their original creator, sound is in stereo, but only coming out of the left side, while the right side stays silent.
I want to split the audio and then copy the left side to the right side (basically turn the whole thing into mono).
I'm using pitivi, but I'm open to suggestions of using another software, as long as it's free and have a Linux version.

Using ffmpeg, a free command-line tool,
ffmpeg -i input.mov -c:v copy -af "pan=1c|c0=c0" out.mov

This copies the video over, and the audio is mono with the first channel of the input mapped for export.
Some players may not be setup to default to a stereo matrix. In which case, you can generate a faux stereo stream.
ffmpeg -i input.mov -c:v copy -af "pan=stereo|c0=c0|c1=c0" out.mov

Did not work, sound is still coming out only from the left side. This is the exact command I used: ffmpeg -i Lesson\ 1.wmv -c:v copy -af "pan=1c|c0=c0" out.wmv and this is the ffmpeg version I have: N-79139-gde1a0d4. Did it matter that I the files are of wmv format?

It should not matter. Show the full console output of your command. Also, try  pan=stereo|c0=c0|c1=c0


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Width and Height troubles
I am new to AE, and hope this question makes sense for you and is easy to answer.
On my website I have some images in portrait format with 2085 × 2560 px. Now I will add a mp4 video file, which will be a simple animation of a logo.
The problem is that the exported file is not in the desired format (2085 × 2560 px); the width seams to be correct but the height is smaller than 2085px.

I tried out different Pixel Aspect Ratios and different data for the height; unfortunately I just could not achieve my wanted result.
What do I have to do to get a video which has the exact format like a 2085 × 2560 px image?
Or did I something wrong while exporting?
Thanks in advance!

If you're using the H.264 codec, you will need your dimensions to be even, so either 2084x2560 or 2086x2560.

Yes I was using the H.264 codec, and I have realized that is was not possible because AE was warning this: "Warning: Output file will be resized from 2085 x 2560 (1.0 PAR) to 2000 x 2000 (1.0 PAR) to meet format constraints." So I tried out the MPEG4 codec, and it worked as I wanted.

I just found out how to solve my problem. The H.264 codec is the issue, it somehow does not work with it and AE gives you a warning: Output file will be resized from 2085 x 2560 (1.0 PAR) to 2000 x 2000 (1.0 PAR) to meet format constraints.

Solution:
I went with the MPEG4 codec and it worked as I wanted.

Did you test if the file works in a browser?

@Mulvya, yes, I converted the mov file into a mp4 file and it works well on the website. Here is what I'm using:
`

`
Update : Try this, precompose all the layers so you have only one layer remaining in the time-line.
Then resize your comp with even numbers only! (2,4,6...) in your height and width composition settings. Apply the same height and width to the layer's scale.
Now, it should go with the H264 codec as well.


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Rolling shutter strobe pattern
I'm trying to implement a vision-based "lidar" system as described here: https://hackaday.com/2016/04/04/smartphone-and-ir-line-laser-measure-distance/
the idea is to capture video at 30fps and pulse a laser at 15hz such that the laser appears in odd frames and does not appear in even frames. By taking the difference between odd and even frames we can isolate the laser line.
when I implemented this, the isolated laser phases in and out with a period of ~1 second. Looking at the raw frames, sometimes the laser is full-brightness, sometimes it is not visible, and sometimes it's at 50% brightness.
Given that the laser is either on or off, I'm not sure why the partial-brightness frames occur. My current theory is that CMOS rolling shutter might not just scan top->bottom like I'd expect, but that doesn't make much sense. I checked to make sure that I'm getting video at 30fps and I'm using a usb camera with the ov9712 chip.

No matter when the camera shutter is active, if the frequencies of the video vertical timing (the frame rate) and the laser pulse are not congruent, you'll see partial exposures as they drift apart.
The solution is to trigger the laser pulse on every other vertical sync time. The details on extracting the vertical interval will depend on the camera, and how to trigger the laser will depend on the details of that device. But some sort of forced sync is the only way to get exactly what you want.

my understanding is that progressive-scan on a cmos camera exposes one row of pixels at a time. So for an un-synced exposure in which the laser is on only half the time, I would expect the laser to appear in the top half but not the bottom. This is fine since in the next frame, the laser will appear in the bottom half, and taking the absolute difference should get the full laser scan.
what I'm seeing would make sense if the camera is global-shutter, so that an exposure in which the laser is on half the time would be the full scan at 50% brightness.

I guess my mental model for the sensor scan is wrong? it would make sense if the sensor was exposed all at once but read one pixel at a time.

@Jack000  The exact effect does depend on the type of shutter (global vs rolling and variations of those) but in any case you must synchronize the flash to the video vertical interval to get consistent, repeatable results.

The shutter is usually only open for part of a frame period.  The most time is spent transferring data.  If the laser fires during data transfer, it is missed completely.


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Premiere Pro: Simple fade for text?
In most video editing softwares I have used, you can
- Click Text Object
- Click Button: Fade In/Fade Out
- Done.

But in Premiere pro, I have to
- Click Text Object
- Open Effects Tab
- Keyframe Transparency 0%
- Keyframe it again 100%
- Keyframe it again 100%
- Keyframe it one last time 0%
- Right Click Keyframe and Set Ease In/Out
- Right Click Keyframe and Set Ease In/Out
- Right Click Keyframe and Set Ease In/Out
- Right Click Keyframe and Set Ease In/Out
- Make sure I dont change duration of the text, or else I can repeat
  whole process again.

Is there no easy way to do this in premiere pro CC?
I know its supposed to be very flexible and fit everyones needs, but I really just want a simple fade effect for the text.

Yes you can set a default transition that uses the ctrl-d key combo. I believe it's set by default to crossfade, which I use. You click your clip, control-d and it'll put the fade in and out on the item.
You can change the default transition in the preferences.
It really is simple.
For bonus points, Control-shift-d works for audio.

Adobe Premiere Pro has a cross-dissolve effect.  You can select it as Effects->Video Transitions->Cross Dissolve.


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Wirecast to wirecast
I am running a broadcast and would like to include content from 2 locations, each location has the ability to stream from wirecast.
Is it possible to stream from wirecast at location 1 to wirecast at location 2?

How far away are your "locations" from each other? How much switching between the two locations do you want? For instance, go live in one location for an hour and then go live from the other the second hour ... I need to know some more details.

One will be from the south of England and one will be from Dublin Ireland.

What is your CDN for delivery? YouTube, Livestream?

Looking at having a few changes from between 5 and 30 mins

Going out to uStream, ideally want the broadcast contained to a single URL

Of course it's all about a single URL. Is there a reason for using uStream? YouTube is free and really awesome because it's YouTube. It offers 1080 streaming with all sorts of lower resolution options for the viewer with just one broadcast stream on your end. We recently dropped Livestream and uStream for similar reasons. In YouTube you can stream two, or more, Wirecast streams to the same "event" or rtmp and set them as "cameras." Then you can switch between them in the back end.

Another idea is to stream, let's say, the event in Dublin to a MacBook Pro in England. Then take the HDMI out of that Mac Book (in full screen) and hook it up to your Wirecast in England and boom! You got your two events in one Wirecast with smooth mixing and graphics! Not too shabby of an idea!

Let me know how it works ... In theory it's a great solution :)

I would use skype from the remote location into the local computer running wirecast then use their screen capturing option to capture the skype video.
The pro version of wirecast allows and input to be RTMP, Web streams and IP cameras. Assuming you have that, you could stream from the remote wirecast and bring it in as a source on the local system.
You may already be aware, but this will add a major delay in the remote feed. Because it will have to be encoded twice. Once from there to local then again locally on your main feed. Just something to be aware of.

Personally I would stream a private YouTube event to a local MacBook pro and take the HDMI out (in full screen) and reroute into Wirecast via a Blackmagic micro recorder as a second camera to mix seamlessly with the other feed.  Skype is clunky and not optimal in my experience.


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Adobe Premiere Pro / After Effects Hard Drive Scratch Disk and Cache set up in temporary situation.
I've exhausted all options before asking for opinions in trying to figure this out, and I'm running out of time by doing all possible combinations and running benchmarks, or setting up projects to see which hard drive set up is working best as I have a job that needs to finished today, with what I have available.
So my usual hard drive set up for Premiere Pro and After Effects is not possible right now, as my main SSD is not working, so I'm left with the hard drives I have left to try and put together a system that will get me through the day as pain free as possible.
I'm making a short introduction to an interview using Premiere Pro and After Effects (not necessarily at the same time for this project), and working with Raw footage converted to ProRes proxies to save me some precious space and speed while editing. I'm running on Mac (El Capitan) and using CC 2015 if that matters to anyone.
Currently for available hard drives at my disposal I have-

My internal 2 TB SSD. (System drive for OS, programs, etc.)
A RAID 0 configured set of 7200 RPM 1 TB (combined size) Seagate's connected through USB 3. I'm getting speed test results of around 147MB/s Write and 148MB/s Read.
A cheap 1TB Western Digital My Passport through USB 3 that is getting speed test results of around 60MB/s Write and 75MB/s Read, although I've seen the write speed jump all the way up to 75, and all the way down to 35, so I've never sure.

So thats what I'm working with for at least the rest of the day. How would you configure your Scratch Disks in this situation?
I was thinking having my Project files on the RAID 0 HD, along with the Source Video, while the Cache ran off the internal SSD. That leaves the Video and Audio previews. Will the My Passport be fast enough to handle them or should I use either the internal or RAID 0 for them as well?
Should I move the cache to the RAID 0 and have the Source Video files and Previews run off of the Internal SSD?
I can't decide so some input would be amazing. Basically the question is, what needs the most and least speed- the Cache, the Previews, or the Source Video files?
Thanks for your help!
-P.J.

Personally, I would ditch the usb3 drive for editing. Assuming you can't buy a third drive I would do your setup like this.
Do a two drive setup.
C: OS and media cache
d: (raid) Media, projects, previews and exports.
I've always followed the advice here and its worked great for me.
https://forums.adobe.com/servlet/JiveServlet/showImage/2-2906955-31395/Guideline+Disks.jpg

Thanks for the advice. I would never use that USB 3 drive normally, in fact I had only used it to transfer files to other computers because it was small, but when I got into this hole I wasn't sure if it was better to use than nothing at all.
The whole idea was that this is what I had to work with the last two days, and had to figure out how to configure it with what I had on hand to finish a job as painlessly as possible.
I just ordered new drives so I should be back up and running as normal within a few days!


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XPS 8900 for Full HD video editing?
I have been doing video for almost 2 years now and currently edit on my father's old ultrabook (i7 quad, 8gb RAM, integrated graphics). Its fine and rendering times are ok, but I recently began toying around with After Effects and the computer begins to lag behind.
I have more or less 1000 dollars to blow and I found a Dell XPS 8900 for around that price. I checked the specs sheet and it seemed really good.
An i7 6700 Quad-Core processor, 16GB of RAM expandable to 32GB, 2TB 7200rpm drive and an Nvidia GeForce GTX 745 with 4GB of RAM.
http://www.bhphotovideo.com/c/product/1187920-REG/dell_x8900_3131blk_xps_i7_6700_16gb_2tb_windows_10_gtx745.html
I don't shoot in 4k in my spare time and when they ask me to, I'm not the one editing the footage.
Is this good enough and fast enough? If not, any recommendations for a PC or a laptop is greatly appreciated.

For editing, I would definitely get a desktop PC, and a custom built one at that, not one from the shelf, as the latter will always be more expensive. Also, this way you only have to pay for the parts you need and can avoid bottlenecks. For example, the PC you mentioned doesn't have an SSD, so hard drive speed will be a limiting factor. Also, the GPU is sub-par compared to the CPU.
Here's what I would recommend, should be doable with 1000 $ (Look out for assembling fees, some dealers will charge you up to 100 bucks, some will do it for 20. You could also do it yourself if you are confident enough):

An i7-processor. Since you should be getting a GPU anyway, you can get a Xeon E3 processor instead (basically an i7 without an integrated graphics unit, it's slightly cheaper). For example, I have the Xeon E3 V1231 v3.
An nVidia GPU with CUDA support. You could get a GTX 970, even though they are somewhat outdated. Alternatively, you could wait for the new Pascal architecture cards, however those will be much more expensive at launch. Alternatively, you could get an AMD R9 390, which only supports OpenCL but might be ever so slightly more powerful than the GTX 970.
A cheap HDD for storage as well as an SSD for fast editing. You don't need a Samsung Evo, it's a myth that those are better than the cheaper brands. For example, I have a 250GB Crucial BX100 and it's working perfectly fine.
At least 16 GB RAM.

It's important that you compare prices and different retailers.


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What's a good alternative term for "live action"?
According to a dictionary, "live action" means:

(in filmmaking) action involving real people or animals, as contrasted with animation or computer-generated effects.

It does not mean "live". Live action can be prerecorded as well as live.
Is there a better term for live action? I would like one that doesn't lead to the confusion with the definition of "live".

No, there is no BETTER term.  But if you really require a DIFFERENT word (for undisclosed reasons), you could perhaps re-define the term "Cinéma vérité".  If we had some clue about the motivation for needing a different term, we may have a better idea how to respond.

The clue is that the term "live action" sucks when talking with people who are unfamiliar with it, they automatically assume it means "live". Can you suggest an edit to my question that would make this clearer?

If people don't understand that "live action" doesn't mean "live broadcast", then why do we think they will understand some other more obscure term that almost nobody knows?  Is it not possible to reply "no, it doesn't mean live broadcast"?   What about "Real Action" or "non-animated"?

"Real Action" and "non-animated" are good suggestions, thanks! I'm not expecting lay people to know all the terminology, I'm just looking for an alternative that I can use with fewer disclaimers and explanations among lay people.

You don't need another term. Live Action is the accepted term for differentiation between, well, live action film and other kinds of movies, such as animation/3D films. It's also used consistently for this purpose, e.g. the Oscars use it in their category names:

Short Film (Animated)
  Short Film (Live Action)

Conversely, I have never seen this term used to indicate a live stream, so nobody will get confused.
There are other terms for feature-length such as feature film or motion picture, however those are rather used to differentiate between feature lenght movies and short films and can also be used for animated films.
If you have a feature-length film, you could amalgamate the terms to something like live action feature film or live action motion picture, but I really wouldn't recommend that.

This doesn't answer the question. Please take it as a given that I need an alternative term. I need to be able to talk to about live action to lay people, and I know from experience that it is confusing, this answer is 100% useless to me I'm afraid.

Well you can't always get what you want .. there is no other term. At least none that is commonly used. Even if somebody on english.SE can find an obscure word for you, people wouldn't understand it any better. Why is this so important in the first place? Just describe what you mean if you must. Take it or leave it ...

I don't think it's very important, it would just be nice if there was a term that worked well both in professional contexts and among lay people. It would be make my life just a tiny little bit of a speck better.

The only other candidate that comes to mind is photographic, as used in the same sense as in Principal Photography. And photography does literally mean the capture of light.
Only hitch is that photography in lay use is firmly associated with the capture of still images.


text:
Difference Blending Option
I saw this cool effect that blends bubbles into each other, and the space that they are overlapping is transparent.

How can I achieve this effect in after effects?

You are interested in blending mode "Difference"
You can use it in "Blending mode" of layer, or on masks.
UPD: Adding screenshot, as asked

Red — Mask Blending
Blue — Layer Blending

Do you mind taking on screenshot on how?

Screenshot added to the original answer.


text:
Multiple HDMI inputs saving on computer
I am recording something with multiple cameras at the same time. I need a set up that will allow me to take the output from the camera and through HDMI or some other output, connect it to the computer and save it. I was thinking of a product that maybe has 10 different HDMI ports and a USB output port that allows me to access, the content of the HDMI cables.
Do you guys think its possible if so how can I do it?

Please clarify whether you want to record each camera SEPARATELY (called "ISO") or whether you are doing some kind of real-time COMBINING ("video mixing").  If you are recording separately, then you will need a very high-performing computer to record multiple video streams.  If you are recording a live-mix then most any modern computer will work. And there are probably non-computer solutions that are easier and less expensive.

Assuming you want to record all 3 feeds at the same time and not mix you could get 3 decklink mini recorder cards: http://www.bhphotovideo.com/c/product/964122-REG/blackmagic_design_decklink_mini_recorder.html I don't know how well it would work recording 3 feeds at once, youd definitely need large ssds.
Alternatively you could record in the camera or use some atomos ninja recorders: http://www.bhphotovideo.com/c/product/759460-REG/ATOMOS_ATOMNJA003_Ninja_Video_Hard_Disk.html I love these and use them all the time.

Even with SSDs, you'll probably need a properly tuned RAID/storage subsystem to handle the IOPS on a single machine. There will probably be quite a bit of processor overhead if you want to compress the recordings, though that will save some on the storage requirements.

You are asking for a Video Production Switcher. This is what broadcasters use to switch between video sources (including multiple cameras, pre-recorded clip playback, computer video, etc.)
There are some software solutions and some hardware solutions. While the software solutions seem less expensive (some even free), they make heavy requirements on the computer, and require in many cases expensive input interface cards with multiple video inputs.
There are hardware solutions which are more traditional for video production. Some of them have H.264 USB output to feed directly into your computer for recording or live streaming.  For example I have several video switchers from BlackMagic Design. Their "TV Studio" low-end model has direct H.264 output via USB.

ok what software can I use with the USB recorders, to manage the live stream layout etc Let's say Cam 1 display as main image, and cam 2 on a window. Similar to this http://signlangtv.org/www/img-tv/ant1-n-ep.jpg

Special effects like combining two cameras plus the "frame" is what the video production switcher does.  That is done BEFORE you get to USB recorders.

Ok the thing is, I have a really powerful computer I can use. I want to just input everything there and use the software to manage it from inside the computer and then stream it.

Then you need to buy enough HDMI input channels for your computer so that you can use a software-implemented video production switcher application.  See: https://en.wikipedia.org/wiki/Software_vision_mixer

I made a extended answer about this similar question, where I recommend Blackmagic hardware, any computer and Open Broadcaster Software.
The answer can be found here.


text:
ffmpeg buffered recording
need some advice to solve the problem
ffmpeg is receiving the nonstop live stream (rtmp source) from camera monitoring entry gates
after trigger is fired (gate/door is open) I need to create the 30sec videofile saved to HDD
I mean this 30 sec as 25 seconds of video before trigger was fired and some 5 seconds after trigger
the similar idea is covered by ffmpeg wiki (https://trac.ffmpeg.org/wiki/Capture/Lightning) but I can't get this working in any command configuration
I was playing with filters, buffering etc too but still no luck ;-((
any ideas would be appreciated

What did you try with filters?

I was playing with setpts or itsoffset, but problem is that I want to avoid processing the video as received rtmp stream in h264 should be directly saved with any processing (just an idea about how it should work)

What you can do is add a blank 30 second segment in front of the camera stream, and then use the method in the ffmpeg wiki.
Basic template is
ffmpeg -f lavfi -i color=black:WxH:r=FPS:d=30 -i camera_input \
       -filter_complex "[0][1]concat[v]" -map "[v]" StreamingOutput

WxH should be set to the camera's resolution and FPS to its framerate.
And the 2nd command which is run 5 seconds after the trigger.
ffmpeg -i Streamingoutput -t 30 snippet.mp4

Problem with this answer is ffmpeg concat doesn't wait for 30 seconds, it completes the concatenation fairly quickly and this fails. Is there a way to force it to concat it per second?


text:
Should I shoot at 1080p if I intend to use 720p on the web?
I'm filming video that will only be viewed on the web at 720p, I'm considering shooting in 1080p in case in future I need to up the quality. I'm going to use 720p at present to keep streaming costs down but in future 1080p could be used when costs fall. Will I loose anything shooting at 1080p with the final output being 720p?
I'm new to video production hence the question.

There is no one right answer to this very general question, but here are the considerations.  Some cameras (such as the Canon EOS DSLRs) have very naive line-skipping algorithms to decimate their normally very high resolution down to FullHD or HD video.  Such algorithms create lots of aliasing noise, which is further aggravated by further image scaling.  Other cameras are more intelligent about how they match the sensor's native resolution to the desired recording resolution.  RED cameras, for example, crop down the sensor so that whether you are recording at 6K or 5K or 4K or 3K or 2K HD resolution (1920x1080) you are using precisely the RAW pixels, not some interpolation or decimation thereof.
Another consideration relates to the actual recording bandwidth of your system.  If you are recording at a fixed rate (such as 28Mbps AVCHD), then a 1080p video will, necessarily, have to employ greater compression than the 720p video, because the 1080p has 2x the spatial resolution of a 720p video (and both have the same bit rate).  If your fixed recording rate is 200Mbps (such as is offered by the Panasonic GH4), that might be so generous that you really are getting very high quality for both 720p and 1080p.  So it depends on whether your camera's imaging system is well within, at the limit of, or past the point of a good compression tradeoffs.
Finally, 1080p streaming might strip out way more quality from your 1080p master than exists in even your 720p master.  In which case a high-quality 720p master might be all you need.
The places where video quality really gets down to the pixel level are typically within the post-production process, pulling keys, doing color correction, sharpening, etc.  Once you have a high-quality master, streaming compression will probably obliterate all differences in your 1080p vs. 720p masters.  Unless you have a notorious camera known for particularly poor quality in the first place.

Thank you this is the sort of answer I was looking for. My camera is a Canon 700D. I think I will shoot in 720p after your answer.


text:
ffmpeg overlay x expression with logical condition
I am trying to create a simple overlay graphic where the overlay moves and screen and changes speed according to time. So I tried a simple
ffmpeg -i input.mp4 -vcodec qtrle -i overlay.mov -filter_complex '[0:0][1:0]overlay=x=if(t<2\,t*3\,t*5)[out]' -map '[out]' -y output.mp4
and got an error code of :
[Parsed_overlay_0 @ 0000003f4e1e2ea0] [Eval @ 0000003f4c0fe5b0] Missing ')' or too many args in 'if(t<2,t*3,t*5)'
[Parsed_overlay_0 @ 0000003f4e1e2ea0] Error when evaluating the expression 'if(t<2,t*3,t*5)' for x
[Parsed_overlay_0 @ 0000003f4e1e2ea0] Failed to configure input pad on Parsed_overlay_0
Error configuring complex filters.
Invalid argument
if I remove the "if" part and just leave a formula it works :
-filter_complex '[0:0][1:0]overlay=x=12+t*3[out]'
I tried playing with escaping of the different characters but it doesn't look like its a parsing error. Any ideas of how to use this correctly? The ffmpeg documentation has a sample for doing font color expression with a logical value here , but any attempt at
overlay=x_expr
doesn't really work as well
please help
Thanks in advance

FFmpeg uses functions, rather than operators, for conditional execution and comparisons, so t<2 is not a valid syntax.
The syntax for your given command would be
ffmpeg -i input.mp4 -i overlay.mov -filter_complex \
       "[0][1]overlay=x=if(lt(t\,2)\,t*3\,t*5)[out]" \
       -map '[out]' -c:v qtrle -y output.mp4

where lt(var,value) is the less than function.

Sure. How did your earlier project - drawtext - go?

hehe nice that you remembered. We ended doing a fade in fade out on the text,  the character by character thing didn't work out. And we ended doing everything in house...not much ffmpeg available for out sourcing.

Here's an example of how to crop landscape videos to square (1:1 aspect), while not cropping portrait videos:
-filter_complex "[0:v]crop='if(lt(in_h,in_w),in_h,in_w):in_h'[out]"

The Q isn't about cropping videos !?

The question is about using logical conditions in FFMPEG - so this is yet another example that people may find useful

This a Q and A site, not a wiki, so the As are supposed to be As for the Q posted.

I actually found it much useful


text:
Simple video editing software that can handlethis
I have around 2000 images (png) that take up around 3GB. I wanted to make a very simple video where each image is displayed for somewhere between 0.1-0.01s
I read online that I should use movie maker. Tried it, but it seems the program can't handle it. Googled quite a bit, and even with some workarounds it still can't handle it.
Went online in search for an alternative (a question here actually) and tried hitfilm. That froze.
So my question is the following:
Is there a free video editing tool that can handle this:

Free
Make a video out of about 2000 images (that can handle this much)
No watermark
Can set image duration to around 0.1-0.01s
I can set fps (or it is high enough to not loose some images)

I'm looking for something simple and that doesn't take that much

You can use ffmpeg, a free command-line tool, to do this
If your images are sequentially numbered i.e. img0001.png, img0002.png...
then
ffmpeg -framerate 10 -i img%04d.png -crf 20 -pix_fmt yuv420p output.mp4

If they aren't sequentially numbered, then you'll have to create a text file of the following format:
file 'ThisOne.png'
file 'ThatOne.png'
file 'ThenThis.png'
...

You can use dir /b /on > list.txt to get the names in alphabetical order into a text file. You'll then have to prefix the file and add the quotes.
Then
ffmpeg -f concat -framerate 10 -i list.txt -crf 20 -pix_fmt yuv420p output.mp4

Each image's duration is the reciprocal of the framerate value, which you can set to any value but for compatibility reasons 8 - 60 is a good range.
The command also assumes that all images are the same resolution. If they aren't, they will have to be made so. You can insert the following option after the input value into your ffmpeg command:
-vf "scale='if(gt(a\,16/9)\,1920,-1)':'if(gt(a\,16/9)\,-1,1080)',pad=1920:1080:(ow-iw)/2:(oh-ih)/2"

This scales each image to fit within a 1920x1080 canvas while preserving proportion and then pads the scaled image to form a 1920x1080 frame.
The CRF value controls the visual quality. Lower value is better but makes larger file. -pix_fmt yuv420p is for producing a file compatible with most players.

Thank you very much. Got an error, but fixed it adding  -vf "scale=trunc(iw/2)*2:trunc(ih/2)*2". Works 10/10


text:
Reducing the frame rate : the smooth video Issue
This is my smooth video.
Video details:
Frame rate=60 FPS
Video codec: h264
Not have any audio stream
I want to convert it to a PAL video, But I can't get smooth video.
How to convert a high frame rate video to PAL format(or reducing the frame rate) Without impact on the smoothness of video?

In order of preference,

Generate animation at 25 FPS and capture it at 25 FPS.
Generate animation at 50 FPS and capture it at 50 FPS. Then, use FFmpeg to generate a 25 frames & 50 fields per sec stream. Stream should be flagged as interlaced. x264 doesn't do interlaced well, so I suggest video codec ought to be MPEG-2 or DV.
Generate animation at 50 FPS and capture it at 25 FPS.


text:
Why Premiere Elements exported project is "jumpy"?
I use Adobe Premiere Elements 12 under Windows 8.1. I have 14 MP4 clips that I cut, join and add transition effects... Something simple.
All the 14 clips are MP4s of the same resolution (640*480), 11 are at 15 fps and 3 are 10 fps. The total running time is around 3h20m.
I want to export the project in 4:3 480p (640*480) at 29.97 fps in MP4. I put all the quality settings at maximum (the export take 6+ hours on a brand new high-end system) but the result is always bad. I see a "jumping" white line at the top of the video. The "animation" is smooth but the details are jumpy.
I found out that if I export in 15 fps instead of 29.97 the movie is OK when it's playing the parts of the 11 clips that the source are 15 fps but the parts of the 3 clips at 10 fps have the jumping problem. It seems the problem originate in the fps upgrade.
In the past I exported this project at 29.97 fps without any problem but at that time the 3 10 fps clips were not integrated.
How can I have an output that is not jumpy?

In the end I just exported to 1080p (with the same export settings) and everything is fine. It sure seems like a bug to me...

Make sure you turn each clip's setting to deinterlace on. If Elements has flicker removal, turn that on as well. Make sure you scale your clips to the right size. But if your source is 10 FPS, converting it to 29.97 is not going to create extra frames, unless you use a plugin or effect like frame blending or twistler. You will simply be playing back 10 FPS at 29.97, meaning each original frame will appear for (approximately) 3 frames at 29.97. 10 FPS is jumpy. 24 was set as the standard a century ago, after 18 FPS had been used for some time and was ruled too hard to watch (flicker). Thus why all the old sports movies look like they run fast... because they play them back at 24. Hope that helps.

My clips at 10 fps looks smooth (it's capture of an old PC game that is really slow) so the 10 fps seems OK. I will look at this later today...

You could try a different final framerate. Try 60p. Honestly, Elements may simply not like the pulldown from 10fps Progressive to 29.97 Interlaced. Or try 24P.  Its an odd pulldown going on, so try different output rates.


text:
FCP retime timelapse image gets blurry
If i retime (speed up) my 4k footage, the image gets blurry.
If i stop the movie, i see a crispy still image!
Why?
I already tried to slow time the footage but it doesn't work
Thanks

It's unclear. Please provide more details. With what tool do you retime?

i retime with the retime button inside finalcut pro

Did it happens after rendering (export), or in the editor? If in the editor, then it is just for faster showing to you result. Try to export video end see result

If you retime the images so that there are more than one images that can land on a frame, your video software will likely interpolate between the two by blending the two frames.  If you play back at 12 fps with zero offset, your video software should play the first image for two frames (assuming 24fps playback), then the second frame for two frames, etc.  If you play back starting with a one frame offset, the first image will play for one frame, then a blend of the 1st and 2nd image will play the second frame, then a blend of the 2nd and 3rd image will play the third frame, then a blend of the 3rd and 4th image will play the fourth frame, etc.  That image blending will make the film look blurry.
Alternatively, say you have 240 frames and you want to play them at 24fps, but you are asking the editor to play them all in 1 second instead of 10 seconds, the video editing software might not pick every 10th image and display it for one frame, but will instead blend 10 images and play that as a frame.  That could also account for the blur.

i solved it! it was the display performance/quality setting to performance instead of quality!

@LorisClara but of course!

@LorisClara Could you put this solution in an answer - possibly describing where the settings are in the app or with pictures of the windows you used? Thanks!


text:
Downscaling 4k to 1080p in Premiere Pro, Image Zooming 2x
When I drop 4k footage onto the timeline in Premiere Pro, I get a 4k sequence. When I change the sequence to 1080p, the image zooms in. This makes sense. I then scale the image back 50% and I'm back to normal.
In every single tutorial on downscaling 4k footage in premiere, no one ever has to do the 2nd step that I do. I thought I solved his issue by going to:
"Edit > Preferences > General" and ticking the box "Default scale to frame size" but it's still happening.
How can I avoid this second step that no one seems to have to do?

You can also right click the media in the timeline and choose "set to frame size" and it will do the scaling for you. But not retrospectively.

Changing the preference doesn't change any clip settings retroactively.  But once you have set it, and then create a new project and a new sequence, and when you freshly import your 4K clip and drop that freshly imported clip onto your freshly created sequence in your freshly created project, it should work as you expect.  And if you right click on the clip, it should have a checkmark next to "Scale to Frame Size".

I didn't follow the above answer, as it wasn't clear on the steps taken - i have played with this 'scale to frame size' etc, but an easy fix for me for playback, was to click the spanner icon, in the programme window, and select 'high quality playback' - you can then do playback in 4k on a 1080p timeline - with 1/4 playback also selected.


text:
Big difference in the video file size after the conversion (.mov to .mp4)
After converting from .mov into .mp4, a video file is greatly reduced in size (.mov - 75,2mb .mp4 - 11,9mb) - does this mean that the converted video degraded (loss of color information, or the information in the highlights/shadows, or something else) or such difference in file size can be lossless?

If it's for playback use, and not further editing/processing, all that matters is if the output quality looks good. Quite likely, the conversion wasn't mathematically lossless. Anyway, which tool did you use, and with what settings?

@Mulvya I used Miro video converter. I need to convert these videos without loss of quality for video editing.
But since I have a lot of videos, I'm looking for a converter that can convert many videos with the same conversion settings (rather than manually convert each video one after the other). Could you advise me a converter which is able to convert a large amount of videos without loss of quality, for Mac?

@Mulvya settings: http://prntscr.com/bbdzgn

Use Handbrake.

@Mulvya Thank you very much! I tried this converter and it gave me the best result compared to all the others. Though the video after the conversion became more than it was)) I probably made a mistake in the settings, I have not yet realized what it was. Anyway, thank you very much!
And I have one more question, I see that I can add videos one by one in the render queue and can use the presets, which makes the process of choosing conversion settings fast. But is it possible to add multiple videos in a queue at once, not one after another?

Not that I know of, but I don't use it much. Make a folder, shift all the files you want in there and select that. As for size, increase the Constant Quality value in the video tab for smaller files.

Let me explain you from scratch.
MOV, MP4, AVI, MKV etc all these are just containers, It is just kind of wrapper which contains audio, video, text, metadata file together as one file. It does not play a big role in the size of a file.
Size of the file heavily depends on audio and video codec and bit-rate of that audio video codecs.
So there is a possibility for file size reduction during conversion.

Reduce in video codec bitrate. While converting video if default/changed bitrate of video codec is less than source file, then it will lead to a reduction in file size as well as quality for sure.[ May not be perceivable by eye ]
Change video codec. While converting video if change video codec to advance video codec of the stream, then it will reduce size but quality will not be degraded.

For example :
Video codec of a source file is MPEG-2 with bit-rate 20mbps and during conversation we convert to H264/AVC with bitrate 10mbps it will have the same quality with half of the size.
So, Below are the popular video codecs generation and improvement.
MPEG-2 -> H264 (40-50% bitrate reduction than MPEG-2) -> H265/HEVC (40-50% bitrate reduction than H264)
Though the more advanced codecs are computationally expensive during video playback. e.g H265 is ~300% more computationally expensive than H264.
During video conversation point 1. & 2. both can be applied
You can view details of audio/video file can be seen using a free tool (mediainfo)
It will show properties of the stream like video codec, bitrate, fps etc.

Thank you very much for this detailed answer! This is very helpful to me!

Worth noting that the computationally intensive nature of h.265 and h.264 make them less suitable for editing. A codec that uses more space for the same perceived quality but which requires less processing per frame might be better. Have a look at Avid DNxHR or GoPro Cineform, which are good, free editing codecs.


text:
Source video has 1GB and the final version has 3GB or more
I've created a small intro animation for my videos on After Effects and created a project on Premiere, than joined the animation and the video from a webseminar.
The webseminar file has 1GB and the intro video with just 13 seconds that has been rendered on AE also has 1GB.
My final video will be uploaded to Vimeo and I only need HD quality, but even this way the file has at least 2.5GB.
Which codec do you suggest?
Another thing, I saw that if I use the same codec from my composition, the rendering process is faster. Is this true? Because a 50 minutes video is taking 2h and a half to render.

For web use h.264, there are lots of web presets in the export media dialogue, or in Media Encoder that you can use. The first or second one should do the job, but if not there's lots of options.

If you're planning on exporting different copies of the video, or you want a copy for archiving then a master in a lossless format or a high-quality lossy codec like proRes, GoPro Cineform or DNxHR is a good idea. Then you can re-encode from this master to the more compressed web versions without having to re-render.
As for rendering times, with an After Effects comp at the start of the encode it will often report that it is going to take a lot longer to render than it actually will - it assumes that the whole composition is going to take as long per frame as the intro does. If you're exporting to h.264 it will take a little longer than other less compressed codecs, generally the smaller the resulting file the longer the encode takes.
Import the After Effects comp using Dynamic Link, that way you don't have to create intermediate render files, and you can change the AE comp without having to recreate your intermediates. Just import the after effects project as you would any other media file, and then choose the composition from the dialog that pops up.


text:
What detailed research exists on the effects of aspect ratio on perception?
I'm interested in the effects of aspect ratio on perception in video, whether it's movies or else, looking for detailed research. Could anyone recommend books, courses, research papers on the subject?
I've looked on google scholar but aspect ratio is a broad subject that has different meanings in different fields, thus I couldn't find anything relevant.

I can't reference any particular books, but I remember a while back a number of well known directors, including Kubrick, Spielberg, and a few lesser known, discussing their choice of frame size for particular films.
16x9 I believe most closely simulates the human eyes; 2.39/2.4:1 is often chosen whether via by anamorphic lenses, or via simply matting, when the director feels the wider aspect fits the theme, story, landscape, or simply preference for how he visually want's to create his film. 2.4:1 allows for greater flexibility in framing simply because it's a wider workspace.
Kubrick did many of his films in Academy ratio, basically 1.33:1 or what many call square. It worked too, I can't imagine Eyes Wide Shut, which was a very recent film, with major actors, shot in anything but Academy. But few these day's are. I don't think you could even crop down this film, in terms of fitting it for 16x9 without really throwing off the overall composition of each and every shot.
Lastly, many films, even when shot digitally, are shot and captured in a ratio which is larger than the final format. This allows final adjustments to be made in Post Production to either vertical or horizontal framing; or both.
Most of today's content is purposed for 16x9 or 1.85:1 Why? It fits. It's the new standard, 99% of TVs on the market and all theaters are able to handle it.
Big budget films, action, music videos, epics, are often shot in 2.4:1 because it looks simply bigger. It's a bigger shot. Wider, more grand. It feels that way. Take any 2.4 widescreen film; and if you can, zoom in so it fills a 16x9, and ask does it look smaller.

The most relevant keyword to add to your search is psychophysics, which is "the analysis of perceptual processes by studying the effect on a subject's experience...".
More directly, there's this SMPTE paper Searching for the Perfect Aspect Ratio.
The paper visits some of the research conducted on different aspect ratios and its take-away is

The research for this paper found no clear indication of a preference
  for any particular aspect ratio for moving images nor any
  physiological reason to favor one over another.


text:
I want to add video noise/grain based on an audio track?
Does anyone know of a plugin that would allow me to add video noise that is based on an audio track ?
Anything at all that would let me do this would be fantastic.

You can convert audio to keyframes. Right-click the footage with the audio, and choose Animation>Keyframe Assistant>Convert Audio to Keyframes, or with the audio layer selected go to the Animation menu in the menu bar.

This will create a new layer with keyframes for the intensity of the audio. You can copy those keyframes on to any property that you want to animate and adjust them in the graph editor, or you can use an expression on the property and select the keyframes with the expressions pickwhip. This means that the audio levels can control any animatable property including parameters for your favourite noise effect.
A useful trick is that you can apply EQ to the audio before you convert it to keyframes and have different sets of keyframes for the bassline and the melody sounds.

Thank you @stib!  To simplify this for anyone else reading, the detailed way to do this is:  right click on your audio and select key frame assistant, convert audio to key frames.  Find the key frames under both channels and copy and then paste them into the intensity of your grain effect.

Added a bit more detail to the answer.

Trapcode Particular is the tool of choice for this. You can generate any type of noise/particles, based on an audio track, and tie the parameters to not just the track, but specific frequencies (so the noise is warped on low bass, or changes color on high frequencies).
There are also a lot of templates you can buy on videohive that will jumpstart the process.

Heres a good example to you youtube video, and the template is downloadable in the description for free. (But you will need the Trapcode Suite).  https://www.youtube.com/watch?v=5dSi_SD19UE


text:
Premiere Pro CC: How to reset control panel group settings
I accidentally clicked on "loose panel group" in the mirror for creating a new title, but there is no button to fix them together again. I tried resetting the setting, but it doesn't work.

Is 'loose panel group' a free translation of whatever the option is labeled in whatever language you're using Premiere Pro in? Because I can't find an option or button that says exactly this ...
Anyway, you can change workspaces in the menu, click Window → Workspaces and select a workspace preset. If you want the default workspace back, make sure to select the Assembly preset (in Premiere Pro CC). If you want to revert any changes you made to the saved layout, select Reset to Saved Layout from the same submenu or press ALT + SHIFT + 0.

Yea, its just an inaccurate translation, because I have the programm on german and couldnt find the correct translation..
But yes, that's exactly the solution for my problem! Thanks a lot!


text:
ffmpeg - map a video to a placeholder? (rectangle/square)
I have a video that i want to map to a "virtual rectangle".
Meaning, i want to create a virtual rectangle by giving it one x,y point for the bottom left corner and one x,y point for the top right corner.
Given those 2 points would create a rectangle, i want to take that video and "map" it to that rectangle. (scale it too if necessary)
From what i know about the 'overlay' filter, you can use only one x,y point to set the position of the video.
But is there a way of doing it with 2 points like i explained?
Thanks!

You would use the template below,
ffmpeg -i base.mp4 -i overlay.mp4 -filter_complex "[1]scale=WxH[o];[0][o]overlay=x:y" out.mp4

So, the overlay video is scaled and then placed at (x,y) measured from top-left of base video and the opposite corner is at (x+W, y+H)

so that means i'd have to provide the scale width and height too right? it won't be done automatically

Yeah, but your desired scenario also requires four numbers. The last two happen to be different.

So i'd have to provide x1,y1 and W,H and only then i'd be able to get x2,y2? There's no way of inputing x1,y1 and x2,y2 and have the W,H calculated automatically?

No. It's the same thing though. Think of W as x2-x1 and H as y2-y1

Haha you're right sorry.. thanks!! You save me every time when it comes to ffmpeg ;)


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Replace image in a template created on After Effects
I've created an intro template on After Effects that has some text and the animation of a masked image. If I import this aep template to Premiere Pro, I can easily replace the text, however I can't find a way to replace the image too.
Is it possible?

I don't think it is.  As you say, you can replace text using Live Text Templates.
If you need to easily re-version comps from AE with different source material, I would suggest looking at Templater.

As long as you're running Bridge, you could keep AE open, and then replace the image.
If you've designed a template. I would recommend in AE using a pre-comp called a drop zone. A custom sized comp with guidelines / safe areas that is nested into the final comp. Then you basically can quickly drop any image into the dropzone composition, align/scale, and it will nest into the render comp.
If you dont want to run AE, having bridge running if you simply set a standard for the picture size, as in same size always, crop for import into AE, and then simply replace the photo file on the disk with the new one, using the same name, it will update on the PPro timeline.
As far as doing a replace command inside PPro, from a linked AE project, is not possible.


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Workflow to ingest files from Zoom audio recorder
I use a Zoom H5 audio recorder, and when I copy the audio files from it I like to have them sitting next to the video files they correspond too.
The problem is the way Zoom stores files: every clip in its own folder. Copying all those files into one single folder can take a long time when there are 100+ clips.
Does anyone know of any software, or workflow in Premiere/Prelude to make this easier?

If youre hopefully running windows, use explorer (My Computer). Navigate to the SD card. In the search box for that window, type *.wav (or whatever extension you used to record).
The window will then display all the WAV files found on the card, without the folder. Select all of them. Copy. Paste to a new folder.
If you encounter conflicts in terms of clip name, use the 3rd command called "Allow Windows to Resolve", which will create v2 v3 v4 of the files which use the same file name.

And what if you're working on a mac...? :-/


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How do I achieve a "throbbing light" effect in After Effects?
I've seen this effect in a lot of lyric video, particularly when the music is quite intense. Please see these videos for references:

There is a constant pulsating/flashing light effect

The pulsating light is just the intensity of the light varying over time. There are various ways of doing that, you could keyframe it (if you had nothing better to do), you could use an expression like wiggle, or the "the wiggler" tool (if you're old school), or you could control it with the audio level of a layer that has audio.
If you're trying to drive the intensity of the light from the audio, then you need to first convert the audio levels to keyframes. Right-click the footage with the audio, and choose Animation>Keyframe Assistant>Convert Audio to Keyframes, or with the audio layer selected go to the Animation menu in the menu bar and choose *Keyframe Assistant>Convert Audio to Keyframes**. Then you can use those keyframes by either copying and pasting to your light's intensity property (and tweaking the values in the graph editor), or using an expression. This answer details how you do that.

In After Effects, I think you'll need a 3rd party plug-in to do this. One option is Trapcode Sound Keys. Another is the Frame Manipulator plug-in from DigiEffects' Buena Effects Pack.
You can do this in Apple's Motion using the Parameter > Audio behavior. Apply it to your audio track, then apply a Brightness filter to your footage and set the "Apply To" of the behavior to the filter's Brightness parameter. You'll need to adjust the parameters of the behavior to suite your audio and video.


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VR vs 360 video
Is there a difference between Virtual reality and a 360°video?
For me, you cannot have a VR without a 360video (and 360 camera). And these 360 panoramas, are they considered VR?
A little broad question but hope I can get it straight.

It is more question about VR term, then about video production. So you better ask it on the http://stackoverflow.com/questions/tagged/virtual-reality or http://english.stackexchange.com/

There is a difference between "Virtual Reality" and 360* Video because they have completely different uses.
360 video is created from multiple streams of video being stitched together, or one very wide camera lens. It will either be viewed as one greatly distorted video stream or in a special viewer that only "shows" a window into the plate and lets you "look around" -with a corresponding drop in resolution.
Virtual Reality usually refers to a synthetic world created in a program of some kind like Unity: Unity Game Development Engine or Unreal Engine
Here some starter information on VR Development
It is possible to merge video and "VR" in the context of movie. What you are really creating is a composite (Visual Effects) shot. Simply put, it involves creating a LIDAR scan of a location. Putting that information into a 3D program such as MAYA and then projecting the combination of elements onto the 3D models created from the scan. At which point you may have a 360 virtual set that you could render shots from.
Industries like firefighters and the military are starting to use realistic VR for training. And I think that's probably the closest to what you're talking about. It's going to be a limited "game" universe where the models are possibly scanned from real-world locations. However there's no reason to use 360 video for these applications, it would introduce more issues than it solved over just getting real textures and images.
I suppose it makes sense to mention what 2nd Life and some games have done with VR and realism.
And what Google is doing with 360 video/images

Okay thanks @integris that brings some light :) but maybe it's just wrong wording here: https://youtu.be/eayh49rTZUM
why are they saying 360 video? Seems to me like complete VR experience, isn't it?

@pepys That is 360 video. "VR" is a misnomer here, but I imagine they are trying to be forward compatible and currently hip. You cannot really "navigate" through this space as they say, these are videos that have a set timeframe which allow you to look around in 360 as I stated in my answer.

360 videos are limited to more-or-less one view point whereas VR allows you to move around, eg you can look under a table and discover something you didn't see before.


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ffmpeg - mapping an audio file with 2 channels to a video file?
I have a video file and an audio file (that contains 2 channels) and i want to map the video to stream 0 of the resulting file and the audio file to the next stream/s.
Since the audio file has 2 channels, would i have to map it to 2 separate streams? (1 and 2 of the resulting file)
Or just one stream?
Finally, how should i go about doing that?
I've only tried mapping with video files so i'm not sure how to do it with audio ones.
Thanks!

Channels are conjoint tracks within a single stream, so a stereo audio WAV has one stream which contains two channels. If this is what you have, use
ffmpeg -i video -i audio -map 0:v -map 1:a output

If they are distinct streams, then the above command will still map all the streams, but for explicit specification, use
ffmpeg -i video -i audio -map 0:v -map 1:a:0 -map 1:a:1 output

Okay i'll try it thanks!
For the first command - what if the video file itself also has an audio stream but i don't want to use it? would that change the command or no?

No, the given commands ignore any audio in the video file.


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Is this as high quality a GIF I can produce from this MP4 using FFMPEG?
I am using Powerpoint to create animations which I then export into a video and crop and convert to GIF using ffmpeg.
Here is the (cropped) MP4 video, and this is the GIF I was able to produce:

To my (untrained) eye, it appears rather grainy, and not terribly smooth. I am wondering if there are options in ffmpeg I can be using thaat will give me a better quality GIF.
Here is the command I am using to crop:
ffmpeg -i in\vlans-3vlans-tag-untag.mp4 -filter:v "crop=1262:423:91:154" in\cropped_vlans-3vlans-tag-untag.mp4

Here are the two commands I am using to convert:
ffmpeg -y -vf fps=35,scale=896:-1:flags=lanczos,palettegen out\PALETTE.png -i in\cropped_vlans-3vlans-tag-untag.mp4
ffmpeg -y -filter_complex "fps=35,scale=896:-1:flags=lanczos[x];[x][1:v]paletteuse" -i in\cropped_vlans-3vlans-tag-untag.mp4 -i out\PALETTE.png  out\vlans-3vlans-tag-untag.gif

I should say, I am not particularly talented with ffmpeg, I mostly put these commands together from googling and other posts on this site. So if any of the arguments I am using are making the conversion worse, I'd also be interested in hearing about it.
I tried the -b 2048k option, and I couldn't tell a difference in quality. In fact, when I ran a SHA256 hash on the output file with and without this option, the result was identical.

I find that ffmpeg does a fairly poor job with gifs. Have a look at gifsicle, I use it to compile my gifs and imagemagick to create the source gifs from pngs I export using ffmpeg. I find it produces higher quality, smaller results, at the expense of a bit more faffing around. http://www.lcdf.org/gifsicle/ and http://imagemagick.org/

The separate cropping step is leading to a generational loss. You can combine that and see.
ffmpeg -i in\vlans-3vlans-tag-untag.mp4
       -vf "crop=1262:423:91:154,scale=896:-1:flags=lanczos,fps=35,palettegen"
       out\PALETTE.png

ffmpeg -i in\vlans-3vlans-tag-untag.mp4 -i out\PALETTE.png
       -filter_complex "[0]crop=1262:423:91:154,scale=896:-1:flags=lanczos,fps=35[v];
                        [v][1]paletteuse"
       out\vlans-3vlans-tag-untag.gif

Hrmm, I'm having a hard time seeing a difference. Here is the image the original way I did it, and here it is using the combined crop/convert step.  The 2nd file is slightly smaller, I did notice. So at least that is an improvement.


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After Effects CS6 Problem
I try to render with After Effects CS6. I have a weird problem. Here render result:

Sometimes, it's show some old frames as you see in video.
Here normal video (rendered with Camtasia):

My AE render settings are default. And this is being every (fresh&new) project. Would you have a suggestion for this problem?
Thanks a lot.

The issue was with Camtasia 8's capture. Converting from the AVI format to a MOV format fixed the issue.


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Yongnuo YN 160S - how to get inside?
My light has developed an intermittent power switch. I've never liked the pushbutton switch anyway, and would like to replace it, but I'm ashamed to admit that I can't figure out how to pry this thing apart without destroying it. Anyone ever done it?

Well, I'm an idiot, or was just really tired the first time I looked things over, because after taking another look today I realized that the shallow circular indentations at the corners of the face piece weren't molding marks, but screw channels with small, well-matched rubber plugs. I'll just leave this answer here for the next dummy... :D


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After effects Timeline display: frames into milliseconds
I'd like to change frames into milliseconds in the timeline.
Right one, it displays seconds, and frames in between. But since, I have to work on a music video, i'd like it to be milliseconds inbetween (base 100).
How to do it ?

Here's a workaround:
Create a left aligned text layer - type a zero. Format to the size and colour of your choice.
Twirl down this layer, twirl down text, ALT click the stopwatch on the Source text property. In the expression field that opens in the timeline, replace the text with:
Math.round(time*1000)+" ms"
click out of the text field into a blank area of the timeline.
The text will now show the time of the current frame in milliseconds.


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best alternative to QuickTime .mov
My company is stripping away QuickTime enterprise-wide, due to Apple dropping support for the format.  I use After Effects and Premiere, and others in my group are on Avid Workstations.  Occasionally when I create a video, I'm handed .mov files exported from Avid Media Composer and Sorensen Squeeze to work with in Adobe software, usually as QuickTime uncompressed.  Now that we are unable to work with QuickTime, going forward, what's the best codec alternative to import clean footage to work with?

Apple is dropping support for the player, so no new releases, but the format remains and can be decoded by recent versions of CC without needing Quicktime to be installed. See
http://blogs.adobe.com/creativecloud/quicktime-on-windows/

Adobe has worked extensively on removing dependencies on QuickTime in
  its professional video, audio and digital imaging applications and
  native decoding of many .mov formats is available today (including
  uncompressed, DV, IMX, MPEG2, XDCAM, h264, JPEG, DNxHD, DNxHR, AVCI
  and Cineform). Native export support is also possible for DV and
  Cineform in .mov wrappers.

http://blogs.adobe.com/creativecloud/apple-quicktime-on-windows-update/

Today we’re pleased to announce that Adobe has been able to accelerate
  work that was already in progress to support native reading of ProRes.
  This new capability is fully licensed and certified by Apple, and
  barring any unforeseen issues during pre-release, these fixes will be
  included into an update to the relevant products in Creative Cloud
  shortly.

You may want to clarify the difference between the QuickTime File Format (the container) and the QuickTime Player since this is bound to be a FAQ in the near future.


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How to import 3D object to adobe without element 3D
I've been trying to import 3D object into adobe after effects. I have element 3D installed but it requests a licence file. And it tells me that my licence file is 'invalid'. Is there any other plug-ins I can use to import 3D objects into after effects?.

yes, After Effects comes bundled with Cinema 4D lite.
https://helpx.adobe.com/after-effects/using/c4d.html


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How to export a .AVI as a sequence of images in Avidemux
I'm trying to simply export every frame of an .AVI movie as a sequence of images (.tiff) or a folder of .jpeg images.
This web page says I can simply select all frames in Avidemux, then go to:
File --> Save --> Save JPEG image
But that only ends up saving one frame instead of the entire selection. Any thoughts?
I'm using Avidemux version 2.6.10

You need to downgrade to 2.5 since 2.6 does not support image sequence export.
Alternatively, you could download FFmpeg and run
ffmpeg -i input.avi -q:v 1 in%d.jpg

ffmpeg -i input.avi in%d.tif

Thanks! Avidemux 2.5.6 totally works.
https://sourceforge.net/projects/avidemux/files/avidemux/2.5.6/


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Export Composition Background in After Effects
I made a lower third for someone else. Of course it needs an alpha channel, but rendering RGB+Alpha results in humongous filesizes. Now I was wondering if you can export the whole thing using a chroma key?
Now the Thing is, I could of course export it while putting a green solid behind the whole thing, but I thought, maybe if I change the composition background to green I would not have to fit such a green solid but everything that is transparent would be green by default. However every time I render it, the background defaults to black.
Is there a way to tell AME or AE to use the composition background colour for the rendered output instead of black?
Thanks in advance!

This is the wrong way to go about it. You should export it with alpha. What are your export settings when you try to do so?

I hope the person receiving your 'green screen' lower third doesn't ever find you in a dark alley. Really, this is not the way to do it. If you can't afford the bandwidth to send the video with alpha, render out the alpha channel as a separate movie and send them both (that's the way things were done when sending a Betacam SP videotape by courier was the means of distribution).

Sadly Stackexchange lets me only mark one answer as the "right one" while all those I got were quite helpful ... so I chose the one with the most information on standard procedure and cutting down file-size
Thanks again to all of you, though

I'd have to back up what has already been said. For best results, you will need to export as a Quicktime Animation using RGB+Alpha. Yes, the file size will be huge.
However, there are things you can do to reduce the overall file size, and these things have to do with how your project is set up and your workflow.

Make your Composition size the size of the lower third, not the size of the canvas size for the end user. If the video being produced is 1080, the lower third will be at max 1920 wide, but will likely only use a slice of the vertical space. So size the comp to that and let the editor place it where it needs to go.
Secondly, render the lower third without the name, have them bring up the name in PPro, now he will only need 1 file.
Having not seen your lower third, I can only assume it animates on and off. Does it continue to have motion while up? If not, render only the build on, and build off. And render 1 frame of the static. Let the editor use the build on, then frame hold the static section, then build off files.
Last, if your graphic does have consistent motion, you can either animate in a way that loops to reduce the length and allow the editor to repeat the loop. Also, and I have done this, is- break the composition down into multiple outputs of animation files which can be different sizes, or loops. Things like glimmers, flares, etc, they may only be a short duration of the overall graphic animation. You can isolate those out and render as separate files.

Yes, your editor will have to layer. But PPro can handle that. He can create a sequence for the lower third, and use it as a nested sequence inside his main sequence to apply the names.
My suggestion is think hard about workflow and output possibilities, and go with, as others have said, QT Animation with Alpha. Anything else will give you sub par results.

Animation is not the only codec that supports alpha these days. For example Prores 4444, while technically  a lossy codec, gives you greater colour depth, and more space efficient files.

Sadly the idea was to have the lower third adjust in size depending on the text using expressions so one file to fit all needs will not be possible.
The height thing is a good call out, though, thanks!
Well, thing is we are all but professionals (it is YouTube after all) and while he does know basic editing I did not want to make it too complicated so he can't mess up.
Thanks for your help!

I hope the person receiving your 'green screen' lower third doesn't ever find you in a dark alley. If it was me I'd be looking to bring the hurt. Really, this is not the way to do it.
Firstly there are more space efficient codecs with alpha channels than the default Apple Animation, try proRes 4444 or the newer Cineform
If you really can't afford the bandwidth to send the video with alpha, render out the alpha channel as a separate movie and send them both. I'm old enough to remember that's the way things were done in the days when dinosaurs roamed the earth and when sending a Betacam SP videotape by courier was the highest bandwidth way of sending material. There's no such thing as an alpha channel on analogue tape.
You can achieve that by adding an output module to the render (right click the output module in the render queue and choose add output module). Change the Channels dropdown to Alpha instead of RGB or RGB+. If you want, you can use a compressed codec to save space (or compress after the render, which is what I'd recommend). Just don't compress too much or you'll end up with blockiness in your alpha channel.

well, ouch ... that hurt.
I'll try that ... I just had hoped to save on filesize since the footage with green BG is just 16 MB or something while the other render settings I tried were 2 GBs or something. Then again it is only for YouTube and I sure am not a professional :D
I normally used .mov but since Quicktime has security flaws now, I would've used .avi
Do you know any place I can read up on rendersettings that keep quality at least semi-decent while keeping the file under 100MBs at least?
(clip is like 10s long or so)

The security flaws in Quicktime are in the Quicktime Player, not the container format so don't be too worried. That said, it's probably best to move away from the format in the long term. Your best bet is to send a high quality mp4 using h.264 encoding. Wind up the quality until you get to your desired size. The best way to do this is to render an uncompressed master from AE, then use Media Encoder or ffmpeg to create the mp4 - that way you can try different settings without having to wait for a re-render.

For best results, you should use an alpha channel for lower thirds. However, certain situations may require your proposed workaround.
With your composition active in the timeline, hit CMD/CTRL + K to bring up your Composition Settings. Double check your Background Color and ensure it is chroma key green:
#00FF00

Now add the composition to your Render Queue in AE and under Output Module, ensure your Video Output channel is set to RGB. This will output your selected background color in any area that is set to alpha in your composition. For partially opaque areas, there will be a slight green tint behind the content, so keep this in mind when using motion blur or opacity fades as you may run into quality problems down the road.
Hope this helps!


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Shooting stereoscopic 360 video
I have a full circle (a ring) of video cameras and i want to create a stereoscopic output (assuming my camera rig does not consist of stereo pairs), i would just need to have a high level of overlap between my cameras? (at least 2 cameras covering each pixel?).
I haven't tried it anything yet but i would still like to know.
Thanks!

Creating just a non-stereoscopic 360 capture setup is highly difficult, unless you are shooting vast landscapes with wide angle lenses.
The problems you will need to factor are far more than overlap.
Yes, you will need adequate overlap for adjustment in post production. But you also need to make sure all of the cameras are genlocked for sync. Shutter speeds will need to match, as will white balance and f-stops.
If you plan on having objects come near the camera (which would be why you'd want 3D), you will need more cameras; because for 360 you want to use high quality lenses in the mid to wide focal lengths.
Your issues will be focus, and mostly, warping as the objects move closer to the camera. Once in post, the objects, unless you are (factoring full frame plane of view) using 50mm or longer lenses, will distort due to simple physics. And will be near impossible to align in post-- especially so with a steroscopic rig.
Im honestly trying to envision your setup, and would think in order for anything like this to work, your camera ring would need to be fairly large; like 6 feet in diameter. Using 16 or more pairs (32 cameras) at the very least. Anything less will not produce appealing results.
The few 360 setups I have seen in person used 22.5 degree slices (16 cameras and 16 projectors).
Hope this helps.

Yes it does help thank you! If you have more information or references for the problems that will occur once objects get closer to the camera i'd be happy to know!


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Motion design liquid simulations?
Are there any free liquid simulation programs that can export to After Effects (through any built in setting or Element 3D), or any free 3rd party plug-ins for After Effects to do the same thing?
An example of a non-free program that does this is Realflow.

Blender is free and has awesome fluid simulation. It won't work with after effects like C4D does, you'll have to render and import the rendered sequences, but we're talking free software here. https://www.blender.org/

Thank you! I didn't realize that blender had the ability to do liquid simulations.

I think is really rare find something for free, especially something massive like proper 3D environments able to export (as you said, Realflow), instead I can suggest you Newton plug-in.


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What software / hardware is used by TV companies to generate a live video feed that can be made up of smaller, live pieces?
For example, I'm watching CNN. Wolf Blitzer is speaking on the background, there's a news ticker feed on the bottom and occasionally, individual video clips are shown on the right to go with the story. How is that all put together, live?

In general, it is done with a production switcher/vision mixer. I believe CNN uses the Sony MVS8000. Specifically, it is a DVE or resizer feature that scales and positions the video. The video is played back from another device, likely a video server, under the control of the newsroom computer system.
They may also be using whatever software that does the real time rendering of the ticker to do the same thing that the production switcher's resizers do. Many broadcasters use renders from VizRT or Orad (now owned by Avid). Whether it is done in the production switcher or in the ticker software is a complex system architecture decision driven by the graphical requirements.


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Joining / Concat DNxHR HQ *without* re-encoding
is it possible to precisely concatenate multiple DNxHR (HQ) videos into one without re-encoding?
It seems that ffmpeg can only handle MPEG streams.

As long as the streams have the same properties - resolution, pixel format, timebase, reference frame count, then they can be concatenated by ffmpeg. Strictly speaking, FFmpeg will concat non-matching streams, only throwing warnings for discontinuous timestamps in the input streams, but that output will not be accepted by most (or any) players.

Indeed, it worked flawlessly with this command: ffmpeg -f concat -i mydnxhrfiles.txt -c copy result.mov


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ND filters. Why variable?
I am a beginner to nd filters. Im still debating if i need a variable filter or not.  If i buy a 6 stop filter nonvariable or a 10 stop filter couldn't i just turn the iso up if its too dark. Why would i get a 6 stop or 3 stop. Could a single 3 stop be emulated by a 10 stop with a higher iso? What woild be the difference.
Also if they would be the same why would one need a variable nd filter. If he could buy a 10 stop and control the iso to move up to a 6 stop or 3 stop
Sorry for the beginner question.

This question is better asked on http://photo.stackexchange.com/

ISO isn't magic. When you turn up the iso you're increasing the gain on an amplifier that is amplifying an analogue signal – the light hitting the sensor – and when you amplify a signal you amplify the noise. Remember that opening up a stop is a doubling the light intensity. To get ten stops of gain on a camera with native iso of, say 200, you'd have to go to iso 204800. So whacking a 10 stop ND (also known as a 'Black Filter' because you could literally use it as welding goggles) on the front would mean that all you'd get is noise soup.
A 10 stop ND is really only useful for the harshest sunlight with a fast lens with a wide open aperture, or for still and time-lapse photography if you want extremely long exposures. It's certainly not the first filter I would buy as a beginner.
A Variable ND filter allows you to change the exposure in bright conditions without affecting other picture characteristics. Increasing the f-stop increases your depth of field, which may be undesirable, and increasing the shutter speed (i.e. reducing the exposure time) reduces motion blur, which may mean more strob-y motion (as you often see in sports coverage), again, this may not be desirable.
So a variable ND changes the exposure without changing the feel of the shot as the other ways of reducing exposure do. One thing to be aware of is that some variable ND filters do cause colour shifts across their range. So if you go for a bargain basement one off ebay buy a Macbeth card at the same time because you will have to compensate in post.

Nice answer. Just for the sake of argument, if you need to use a cinema camera with a base ISO of 800 and a wide aperture on a sunny day, you might easily require 10+ stops of ND.

Good point, but I somehow don't think the OP is shooting on a Red Dragon with a Schneider Xenon on the front.

He could just be using a Blackmagic Cinema Camera with a Sayang lens...

I use a BMCC, and I was going to say I've never needed more than 6 stops of ND, even shooting in the Australian outback, but then I checked my variable ND and it's 8 stops. So I'm completely wrong there. With faster glass than my usual Canon 16-35 I might just need a 10 stop ND. I'll edit the answer.

Get one ND filter and one A7SII ... :)

@A.J Urgh XAVC? No thanks. I'll stick to my BMCC - who needs to expose correctly when you're shooting dng?

My previous comment was half sarcastic and half real... but external recorders record .mov out of HDMI if you're super concerned, plus the benefit with the A7SII is that it is the best low light camera EVER. Just because you shoot in dng doesn't mean you don't have to have the "right" settings or camera for a given situation.


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After Effects on Mac: Use touchpad to scroll like in PS or Illustrator
In Photoshop and Illustrator I can 2-finger scroll on the x and y axis. For zooming I can pinch-to-zoom which works seamlessly.
However, Adobe After Effects reacts totally different to this: Pinch-to-zoom results in zooming into the top left corner so the video output ends up "flying" out of the lower-right corner of the screen and two-finger-up-and-down-scroll zooms at the center of the video. two-finger-left-and-right-scroll, instead of moving along the x axis, has no effect whatsoever.
I could get used to that if I worked on a PC but why can't I make use of the wonderful touchpad on my mac? It works in other Adobe CC products that I own, so why is After Effects behaving so weird? It's not just that it behaves different, I see no reason why sidewards-moving is not working and why anyone would want to zoom into the upper left corner of their screen.
Example:
This is what happens when I pinch-to-zoom. The black rectangle in the lower right corner is the video and instead of zooming into the video, pinch-to-zoom leads to putting the video out of sight because it zooms into the top left.

I hope I've written this post somewhat understandable, it's pretty hard to explain but here a little summary.
What I want:

2-finger-touchpad-move: move along x and/or y axis
pinch to zoom: zoom into where my mouse pointer is
(like in Photoshop or Illustrator)

What I get:

2-finger-touchpad-move: zoom into video
pinch to zoom: zoom into the wastelands of the screen, away from the video

Maybe it's just some settings that I am unable to locate but I also googled for the issue and the only results are people asking about how to create zooming animations.

It's so weird the way all the Adobe apps require different muscle memory to do the same thing. Even things that are the same like panning around a work area or zooming. I understand it's because of the history of the apps, but Adobe's acquisition of AE was over two decades ago, they've had time to standardise it.
Until they fix this (and don't hold your breath) you'll have to learn the AE way of navigating your comp window: hold (don't tap) the spacebar and click-drag with the left-mouse-button / single-finger-trackpad to pan and scroll, scroll-wheel / two-finger-slide to zoom. It will zoom to the point that is in the centre of the comp window, unless you hold the alt key while you're zooming in which case it zooms to the cursor. If youy want to zoom right in to the frame level press ;, press it again to zoom out to the whole comp.
Also useful are the , and . keys which zoom in and out (it makes more sense if you think about the < and > symbols which also share those keys, but you don't hold shift) and ? which zooms to fill the comp window. You'll find that AE works best if you work two-handed. Dominant hand using the pointing device of your choice, the other working the keyboard. Efficiency in AE is all about keyboard shortcuts.

Wow thanks for including all the keys! Will defo take some time to learn it but it'll be worth it I hope

Hey I forgot about alt scrolling. I hardly use it becaus I work with a wacom and huge monitors, but it zooms into the mouse position. I've edited the answer

As far as I know, it sadly is not possible. Maybe through third-party plug-ins, but it behaves the same way on windows. Maybe if we bug the after effects twitter account long enough about it they will listen, but for now they have failed to answer my tweets, so I think it really is not possible at the time ...