If one should render out a cryptomatte pass and uses it for compositing it is all ok. Works great, a bit slow but great.
Should there be for some reason be a change in for example the animation, a rerender is needed...one can NOT replace the new rendered result in post
because cryptomatte randomized ...

Same here,

The cryptomatte feature is a usefull tool but when comping and re-rendering a pain to work with.
I didn't changed a thing but the animation and when reloading the img seq I can set the comp up from scratch..
Fix the randomization please!

Thanks, that almost was the problem.
In the screenshot I added, I put a plane on the floor and used the same settings as you said in the shader so it could work as geo to interact with.
But as you can see when I render there are borders which are not the desired outcome.

Hey there,
I have searched the forum for some more insight into frontal projection, I need it for some vfx.
I have a background and need the floor to be projected to show in the reflection of an object I use in the scene.
With a lot of matching I get somewhere with the perspective projection but it ...