I’ve never really played with either of these. I did use ObjectID some (considerable) time ago in a single specific project, though the need was made redundant with Blender developments, and so I haven’t used it since.
Now, I have a scene where, in compositing, I desaturate the final render a little, though I had a single texture that I did not want desaturated. Enter Material ID. Does the job a treat.
How does this stuff not get more attention?
Most of times, these IDs are less practical than Cryptomatte and AOVS for compositing tasks.
The real interest of IDs, nowadays, is to use them in nodes for geometry or shading before render and compositing work.
What do you mean?
The feature is still there, what kind of “more attention”?
I meant generally in the community. There’s so much that can be achieved with it.
As for Cryptomatte, wouldn’t work in my use case. It’s a single material on a multi-material object that I want to mask, and not the whole object itself. (It’s not the use case here, but similar to if you fully desaturated a character, single mesh, but left fingernails and lipstick bright red).
Cryptomatte would work in your case. It is providing 3 levels (Object/Material/Asset).
And AOVS are allowing to be even more specific and master components of materials.
Oh well I have a nodegroup to make the poor’s man Cryptomatte, based on object IDs 