The way I do this is simple:
Create a text layer, type in all your credits. It’s going to be way bigger than your comp size, so you’ll have to move the layer around a bit until you get your formatting right.
Then centre it (or wherever you want it to roll), place it off-screen at the bottom for the first frame of the comp, add a keyframe. Move to the time in the timeline that you want to be the duration of your roll – say, 20 secs. Add a keyframe. Move the credits text layer up until it’s off screen at the top (up arrow will ensure no drifting left or right, shift+up will be bigger increments).
You now have a 20sec bottom to top credits roll. To adjust the speed of the roll, just drag the second keyframe back or forward.
That’s my way, but there’s always several ways to do things in AE.
Enzo Tedeschi
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Editor
Sydney, Australia