Removing Alpha Channel in Node Editor five month old newbie who's having some fun, here. I've been experimenting a bit, and got a problem. I was following this tutorial
from Zacharias Reinhardt on how to create massive background forests via alpha channels.
Seems to me to be the best method there is, if you're aiming for not too much processing.
https://www.youtube.com/watch?v=BtUS8QTsVZA

And then I got stuck in the node editor when removing the black alpha channel part of the png.
I'm 99% certain I did everything exactly like Zacharias showed in the tutorial,
but somehow, I'm getting a somewhat different result? And yes, RGBA was selected during export of the original file.

I've added a screenshot of the section in the tutorial and a screenshot
of what I've got on my screen. Any help would be greatly appreciated! :)
To help troubleshooting, add an emission node and set it as alpha channel viewer, because it looks like there is an uncorrect alpha channel.

An useful shortcut for this procedure is to enable the Node Wrangler Add-on and Shift Ctrl click on a node a couple of times to temporarily view its output values.



Also checking the image in a 2D app (Gimp, Photoshop) could help, because the Blender setup looks correct.