Cryptomatte doesn't work

[gianluca_menti1]

Hi guys,
I'm new to Vray for Rhino. Today I installed this render engine for Rhino. Nice tool.
But there is a problem: I can't obtain a Cryptomatte image after activated the right Render Element.
I followed that steps:
1. turn off interactive render and progressive render
2. activate Cryptomatte in Render Elements, ID by Material Name
3. launch render
4. In V-Ray Frame Buffer I can see the Cryptomatte image (see Crypto1.jpg)

After saved in a EXR file the layers, when I open this file in Affinity Photo, I find a totally strange file, not showing the Cryptomatte element...



In few words... Cryptomatte layer element doesn't work properly... What was wrong?

Thanks (and sorry for my terrible English)...

[Peter.Chaushev]

Hello, gianluca_menti1 ,
Thank you for describing your problem in such detail.
Unfortunately, it appears that Affinity Photo does not support Cryptomatte yet.
The mask data is serialized in your rendered files, however, you need an image-editing software with Cryptomatte support to access it correctly.

Kind regards,
Peter

[gianluca_menti1]

Hello Peter,
Today I discovered that Cryptomatte works, but only if the file output format is JPG. With Tif, EXR, Png the Cryptomatte output will be corrupted. If I choose JPG file, with separated channels, the issue disappears.
Affinity have no issue with Cryptomatte produced with Blender (I used it for many months) in EXR file format.

This is VFB Output in Rhino:


I saved the Cryptomatte channel in 3 format: JPG, PNG and TIF... Only JPG works (with Affinity)



JPG file is correct, no issue... the others are unusable.


This is a EXR file created with Blender, opened in Affinity with no issue. I presume Vray for Rhino may have a problem.