OCIO / ACES should be 32 bit only

Report · Mar 27, 2023

In After Effects 2023, choosing the new OCIO color management engine sets the project working space to linear ACEScg. The gamma options are greyed out so there is no confusion and no manual setting for linear compositing. This is all great!

But the user can still choose between 8 / 16 / 32 bpc.

OCIO / ACES should be 32 bits only. You cannot do linear compositing in 8 bit, and AFAIK if you try to work in 16 bit then you'll get problems with overbrights and potentially very weird color artefacts.

So - if you choose the new OCIO color engine, then the project should be locked to 32 bits, just like the gamma is locked to linear.

Report · May 24, 2023

Not exactly.

You can work in linear space in both 8 and 16bit.

You loose overbrights, and in 8 bit you can get banding.

So obviously, when working in ACES you should be working in 32bit but 16 and even 8bit are still usefull.

Why?

RAM!!!.

You can fit 4 times more frames in your preview in 8bit than in 32bit.

You don't need to work in 32bit while doing roto, or tracking, or general compositing. Only when you deal with colors and blurring (yeah) you HAVE to do it in 32bit, because 8 and 16 bit might give you different results. But after you're done, there is nothing stopping you from going back down to 8bit to do some other stuff.

You just have to remember to change it back to 32bit before rendering - which AE will actually remind you when you hit render.