Increase fade in/out from/to black time in iMovie 10.1.4?
No, you cannot change the fade time in Settings &gt; Fade Out to Black.

Even the manual Transitions &gt; Fade to Black does not work well because it fades to black too quickly (in about 1/3 of the duration of the transition), then it's black for the remaining 2/3 of the duration.

If you want a linear fade to black that you can set the duration, just add a Cross Dissolve to the end of the timeline and set the Duration of transition.