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Cryptomatte affected by Aperture Shape and Optical Vignette

Posted: Thu Dec 28, 2023 2:58 pm
by Maxter
Hi,

my problem is when I select a cryptomatte ID in After Effects and set the cryptomatte output to "matte only" the selected ID gets grey but not white.
cryptomatte_aftereffects.JPG
When I change the output to "matted RGBA" my selected ID gets half transparent.
matted RGBA
matted RGBA
I'd never had this issue before.

My working space is Aces
After Effects version 23.2.0 with native Aces support
I'm using Octane 2023.1.1 and exported the renderings as EXR(Octane), 16 Bit, Multilayer, Piz Compression

I couldn't find a solution online for my issue. I switched to 32-bit, changed distributed rays to non-distributed without pixel filtering, increased the cryptomatte bins to the maximum, and changed the saving to single-layer files. However, the transparency in my cryptomattes is still persisting. I even loaded an old project that I rendered in a 2022 Octane version, and those cryptomattes are working correctly.

I'll upload a render image of my current project:
https://we.tl/t-4Wzk1eEJJB

UPDATE:

I identified the issue. It seems to be related to the custom aperture shape I selected for my camera.
custom aperture
custom aperture
Iris_Clean.png (11.46 KiB) Viewed 1116 times

When applied, it affects the brightness of the cryptomatte and embeds it, resulting in transparent mattes:
cryptomatte_custom_aperture.JPG
That's how it looks with a regular aperture shape from octane:
cryptomatte_circular_aperture.JPG
When adjusting the optical vignetting distance, I've observed that the vignetting effect is also affecting the cryptomatte:
cryptomatte_circular_aperture_with_optical_vignette.JPG
I guess it is the excact same problem. Is this a bug or limitation of Octane :?:

Re: Cryptomatte affected by Aperture Shape and Optical Vignette

Posted: Fri Dec 29, 2023 10:21 am
by bepeg4d
Hi,
to remove DOF, you need to go to Render AOV gropu tab and change the "Info sampling mode" to "Non-distributed without pixel filtering", but it works only for Octane Info AOVs, here is with Mat ID, but as you can see the Universal Optical Vignetting is not removed:
IMG_0709.jpeg
And it doesn't work with Cryptomatte AOVs:
IMG_0710.jpeg
So, to obtain correct Cryptomatte AOVs, you need to re render the scene by switching the camera from Universal to ThinLens, set the Aperture to zero, and the Max Sampling to 1 in Kernel panel.

ciao,
Beppe

Re: Cryptomatte affected by Aperture Shape and Optical Vignette

Posted: Fri Dec 29, 2023 12:45 pm
by Maxter
bepeg4d wrote:
So, to obtain correct Cryptomatte AOVs, you need to re render the scene by switching the camera from Universal to ThinLens, set the Aperture to zero, and the Max Sampling to 1 in Kernel panel.

ciao,
Beppe
I already thought about that workaround. I guess I'll do it this way.

Thank you Beppe