@xanderscores Novation Impulse is also good with its Semi-Weighted keys and aftertouch, Novation launchkey is lighter, it's good to play faster lines for example.
I found this pros&cons review that could help you, have a look:
@Jessicarosewil I'm not entirely sure if it's possible on iMovie because it has limited options.
Do you any have other softwares ? If not, you can DM me your portrait film and I will try to solve your problem
@Jessicarosewil I think you have to first specify which size you want your video to be according to the size of your photo otherwise it will crop by itself. Let me know if it works ! =)