get bad background with simple light on a solid background

[Greg Gesch]

Hi Bernard, it’s called “banding” and is a common problem. This tutorial might help:
https://www.bing.com/videos/search?q=after+effects+banding&view=detail&mid=C5AB07F807B05EF84AE0C5AB07F807B05EF84AE0&FORM=VIRE

[Mike Sevigny]

Hey Bern,
As Greg mentioned, it’s a common problem.

Try creating an adjustment layer and adding the Effect ‘Add Noise’. Set it to a low number like 3% and it should smooth out your gradient. ‘Add Noise’ is a lot more cost effective than ‘Add Grain’.

Mike

[Casey Drogin]

The smooth gradient background is displaying a common glitch called “banding.” Essentially, your gradient is so smooth that After Effects is having trouble telling one grey pixel from another. Here’s a quick breakdown that goes over why that happens and how to fix it: https://www.rocketstock.com/blog/removing-banding-in-after-effects/

[Richard Garabedain]

Just keep going with your project. it will go away once more stuff is on screen