It’s 2026. Can we get a proper Cryptomatte AOV this year? I am not sure why this has not been added yet. The current CRX workflow is not a workflow. We need an AOV that can be rendered out with a sequence and used in compositing software like Nuke or After Effects.
Every other render engine has this. I am not sure why there is such a hold off for Corona to have it added.
Completely agree, the current CXR requirement is strange and seems like a hacky solution. It would be much easier to save an EXR from the frame buffer without any additional steps, Vray and Unreal Engine and others have this figured out.
Don’t forget to add / vote for this on the Ideas Portal, which is the ultimate source for all feature requests these days. Thanks!
I am not sure why this is a wishlist item and not a mandatory feature for a production render engine. I mean, we got toon shading before we get an industry standard AOV. ¯_(ツ)_/¯
Mostly because Toon Shading has been requested on and off for the last 10 years so is a more long standing request, and because the solution here is in fact likely rather hard - since we run through Max and C4D save routines we don’t have full control over the writing of EXRs etc. (V-Ray, btw, have written their own save routines afaik). This means it is possible we’d need to write our own save routines from scratch to enable this request (the devs can say for sure if and when this gets picked up from the Ideas Portal), which would make it non-trivial and affecting a lot of other things along with it.
Also for some time cryptomatte was initially only or mostly used in VFX, which Corona does not target, which also made a difference in how it was prioritized for V-Ray since VFX is targeted there.
Just for your understanding on how and why things get prioritized 
EDIT - and of course, all who want this, do vote on the Ideas Portal so we can accurately see it’s importance to you all!
Same, it doesn’t feel wishlist-worthy, it simply should have been this way from the start. One of those ‘how/why did this become the accepted worklfow’ things
“Cryptomatte support” is one of listed features, so there’s nothing to request honestly.
Fundamentally, it should conform to the “cryptomatte_specification.pdf” otherwise, it’s just another “Known limitation” or a bug. It’s that simple.