I just stumbled about a problem, I seem to be unable to find a solution (or maybe there is none due to the nature how it is created) or maybe I've never had the case where it was obvious and it was there all the time.
I am doing for example a simple scene a cube on a plane in Cinema4D with Octane 2022.1.1 R2. I rendered the beauty and the passes file with the cryptomatte layers (material and geometry node for example). (Both *.exr 32bit).
I open these files in Photoshop with the Exr-IO Plugin. When I now look into my passes-File, I get all my cryptomatte-layers for each object (white on transparent, or white on black, doesn't matter). So far so good.
But, if I activate all the layers and put for example a black layer in the background. I got around every object-layer a 1 to 2 pixel edge.
But, and I think I recall that in the previous 2021 version, when I clicked on the premultiplied alpha in the camera imager, this behaviour wasn't there (or maybe it was, and I never had the case where I needed an adjustment layer to color an object complete White and not have a thin pixel line around it when it is a scene where it would be obvious that the mask layer didn't fit 100%).
Now, it doesn't matter what I choose from the render settings menu (where the new premultiplied alpha settings went) - linearized, encoded or none (Can also somebody explain me the difference, I can't see any between them). All the time the same behaviour that I get masks for my objects with a one-pixel too small edge.
I attached a picture, maybe that will make it clearer what I mean.
Maybe it is a behaviour of Photoshop and to seperate the layers it needs to split it with a pixel line between the single layers.
And maybe in After effects it would not occur, but at the moment I don't have an animation project in the pipeline where I need to use cryptomattes, but in this case I have to work with Photoshop for a still.
But I also know in past projects, I had this small pixel-edge in After Effects when I forgot to render the sequence out with "premultiplied alpha" checked.
And this time, it doesn't work and I get in this case these result like in the the example picture.
Has somebody the same behaviour, or didn't anybody discover it yet? Or am I doing something wrong with setting up and using my passes-EXR in Photoshop?
Thanks a lot!
Best regards
- Here you can see the thin black line between the 2 cryptomatte layers.