Proper workflow for cryptomatte

[jayroth2020]

Well we're trying to achieve this desired "grouping" in one render. Beauty + all the desired masks in crypto. Using ocol with red, green and blue channels doesn't give you that many groups to work with.

So far I haven't found a way to tell crypto "yo, group these 5 objects for me into one mask and these 13 objects into another mask and so on...". Using CryptoMaterialNodeName is a stable way that doesn't change seed BUT it's not great for many other cases because the user can't group stuff together as he wishes (renaming materials to force a crypto group seems like a crazy way to do it).

You can do this in the comp app of your choice, which is the original design intent of cryptomatte. Use each tool for its strengths. In Octane, cryptomatte is used to create mattes for isolation of target elements for picture assembly in your comp app. Octane allows you to set those isolations via cryptomatte and does this very well, in several different ways. Beyond that, use the proper tools in your comp app to take you the rest of the way.

[bepeg4d]

Hi ,

in the latest 2020.1.2 when enabling cryptomattes I only get transparent images.
Sometimes with edges where the motionblur appears. the rest is transparent.

When switching back to 2020.1.1 it works as expected.

It happens in every scene. Even with a simple box in it.

EDIT:
I just noticed it is also happening in 2020.1

Please set the Live View to LDR-(bit for checking Cryptomatte passes, they are not visible if set To HDR/Linear/ACES.
Anyway, they are saved correctly from Picture Viewer.

ciao Beppe

[Powel2097]

That did the trick,.
thank you!

Please set the Live View to LDR-(bit for checking Cryptomatte passes, they are not visible if set To HDR/Linear/ACES.
Anyway, they are saved correctly from Picture Viewer.

ciao Beppe[/quote]

[ceen]

No, I just started the rendering again. If I can spare some time, I'll try some scenarios.

But even if I change the Objects or material count, isn't it possible to maintain the already given color plaette? Say my scene is finished but the client wants one more treet far in the back. I think its a no go if adding the object screws up my entire Postwork I already did, there has to be a solution. I can't believe big studios could work with this limitation.

Maybe other users could share there experiences with cryptomattes...?

I didn't see this case on my sample scenes. Have you changed the count of objects in the scene while rendering?

Yup, I can confirm this. Simply re-sending the exact same scene to Octane generates completely new Cryptomatte colors. It's quite a pain having to re-assign the mattes every time a new render is updated in AE, so for the most part, we don't bother with Cryptomatte. The crypto passes are there in the picture viewer in C4D.

Here's a sample for what it's worth, Ahmet.

Hi,
I have massive problems with Cryptomattes in 2020.1.4. I rendered frank's file here and as soon as I want the multilayer EXR in PS I get the message "No cryptomatte layers in file". On another rendering I have the transparent issue mentioned above. Is there sth broken or am I missing sth.?

[bepeg4d]

Hi,
you need to use EXR-io to be able to see and use Cryptomatte passes in photoshop:
https://www.exr-io.com/

ciao Beppe

[ceen]

Yes... I Know. I had to clean the old version first berfore the new worked. Was an installation thing sorry...