Does Crytomatte work in non EXR (32 bit) files?

[Alex_M]

This is what I get when I save the cryptomatte channel as JPG (see below). How do I use this given that the edges are not anti-aliased? I am looking for a way to save out the black and white mask that you see when you use the "show preview when selected" option.

[stezza]

If comping in photoshop you'd need to save out as multi exr and use the plugin @ exr-io.com/
This can split out all you mattes into layers.

[Alex_M]

Thanks for clarifying. Unfortunately, I don't use Photoshop, but Affinity Photo, so I can't use the exr-io plug-in. I guess there's no other way to extract a black and white mask from V-Ray with cryptomatte? It would have been great if we could do this given that we can already preview the cryptomatte selection as a normal black and white mask in the VFB.

[stezza]

Use a multimatte render element make sure you turn Use material ID to ON. then input your number.
Select the material you want masked and assign material ID, give it that same number.
This will render a mask for that material.

[Alex_M]

I already use multimatte, but it's not as flexible as cryptomatte. With cryptomatte you don't need to prepare things for masking in advance. You just render and then pick any object or material that you want interactively.

[SonyBoy]

I would think that you'd at least run into possible anti-aliasing/premultiplication issues using cryptomatte passes and color keying? It's not really how they're intended to be used, is it??