Cryptomatte behing a glass and on a reflective surface

[fraggle]

Hello,
what's the correct way to get crypto working behing a glass for a mirror surface?
In fact I even can't get crypto working for object behind the glass (witch is logical), so what should I do to pick object visible in a mirror (I'm talking about relfection behind a glass, not the reflection of the glass itself) behing a glass?
Thanks

[nikoleta.garkova]

Hey fraggle,

Cryptomatte cannot be propagated through reflections/refractions - this limitation has also been mentioned in the docs portal here: https://docs.chaosgroup.com/display/...RayCryptomatte

To workaround this, you might want to use the MultiMatteElement to generate the desired masks behind glass/in reflections. Just make sure that in the material's Reflection/Refraction parameters, 'Affect all channels' is selected.