(Open) [HOU-1499] (Open) [HOU-1495] (Fixed) [HOU-1424] Cryptomatte | Artifacts on edges / Sawtooth

[Mr.Hoo]

Hi,

I am getting strange behaviour with out of the box cryptomatte, see attached images. Everything facing background is fine, but contact or overlapping geo is having that issue.

Houdini 17.5.229
Vray Build: Build number: 5542 hash: 02be50d from 25 Oct 2019 04:21
but newer ones also...

I am rendering to exr and I think everything in the ROP is quite basic.

Thanks for looking into it, I am quite addicted to them

Cheers
Dominik

[bdancer]

Are those VFB screenshots? Those are only for preview purposes. Have you tried opening this in Nuke for instance?

[Mr.Hoo]

no, these are actual Nuke screenshots. the right one is an alpha extracted from the cryptomatte node..

[Mr.Hoo]

double post - can be deleted

[bdancer]

Are those separate objects?
Or is this cryptomatte in user attribute mode?

[Mr.Hoo]

the cryptomatte is in "material" mode - all different primitives in one geometry sop
Maybe our cryptomatte plugin is out of date?

[yolov]

Hi Dominik,

This still looks like the preview channel. For cryptomatte, V-Ray will generate the preview (which looks like your screenshots) and a few other cryptomatte channels that hold the actual data.
The preview is not used by the cryptomatte plugin.
If masking works fine without artifacts or other issues, then the data was correctly generated.
You could also view the rest of the cryptomatte channels. Do they look OK? If you use the cryptomatte nuke node and mask objects out and grade/correct them in any way, are there any errors in the result?

[Mr.Hoo]

Hi,
no, its actually an aplpha generated out of a cryptomatte node in Nuke. I know about the "preview" mode.
But the generated alphas look the same.
here is an exr
https://we.tl/t-NfjAe2khC4

[Mr.Hoo]

Btw - I am also using the OpenEXR IO Plugin for Photoshop, which results in jaggy masks too - so Nuke and PS have the issues

This one seems to have the same issue:
https://forums.chaosgroup.com/forum/...re-not-working

[yolov]

Thanks for the update, we'll have a look and get back to you.

[Gosho.Genchev]

Hey, Mr.Hoo , thanks for the Exr! We managed to isolate the issue - I've tagged the forum thread with the ticket number and will ping you once we have the problem resolved.

All the best!

[Mr.Hoo]

First of all, Happy new year everybody!

Any news on that issue so far? Have some projects in the pipeline and would really appreciate working cryptomattes.

Thanks and cheers
Dominik

[Gosho.Genchev]

Hey, Dominik,

there is a fix in the nightly/nightly builds. If you have access to those - the issue should be resolved for you. The fix is not in the nightly/stable builds yet, though.

Cheers!

[Mr.Hoo]

Hi gosho, thanks for the info! I'll look into it

[Mr.Hoo]

Hi,
I tried the latest nightly/nightly and it works perfectly now!
Thanks
Dominik