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
Are those VFB screenshots? Those are only for preview purposes. Have you tried opening this in Nuke for instance?
no, these are actual Nuke screenshots. the right one is an alpha extracted from the cryptomatte node..
double post - can be deleted
Are those separate objects?
Or is this cryptomatte in user attribute mode?
the cryptomatte is in “material” mode - all different primitives in one geometry sop
Maybe our cryptomatte plugin is out of date?
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?
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
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:
Thanks for the update, we’ll have a look and get back to you.
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!
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
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!
Hi gosho, thanks for the info! I’ll look into it
Hi,
I tried the latest nightly/nightly and it works perfectly now!
Thanks
Dominik
in case you want to see the exr, here is the link: Dropbox - Error - Simplify your life
Hey, @maxtrks28 ,
Please correct me if I’m in the wrong here. So, I’ve consulted a couple of colleagues with more experience in compositing and the general consensus is that the result appears correct. You may want to increase the Subdivs further to clean up the aliasing in the ice cubes in the background.
I played with the EXR you gave us using the cryptomatte as a mask for a Color Correction node. I’ve attached a short video here: https://drive.google.com/file/d/17D\_D\_d67JuQ1vZ05YdftEmV1-MbqgKG3/view?usp=sharing
Regarding your first post - I assume this is a screenshot from the V-Ray Frame Buffer ? If so, we’ll try to reproduce this here and fix the preview in the VFB although if it’s not blocking your work, it may take a while.
Cheers!
Thank you for the quick reply, yes, that first image was from vfb, but the result is basically same when i bring it into After Effects. What i was doing it masking out the Light at the back, not Color Correcting. Is it possible for you to try that? it is the background. It may be acceptable for color correcting, but it may have issues masking it out.
To make sure it is not me, I also tested the same scene with Redshift.
I rendered in Vray at Min/Max subdiv 1/24, which took 2:49 to render.
Rendered in Redshift fairly similar settings (I think), took 1:13.
If you can, please check out the exr files from both VRay and Redshift, specifically, masking out the background. Here are the links:
V-Ray exr: Dropbox
Redshift RBG exr: https://www.dropbox.com/s/luq2osu5sufj0m2/RS.Redshift\_ROP1.0001.exr?dl=0
Redshift Cryptomatte exr: https://www.dropbox.com/s/hox7jdh9at6nnzz/RS.Redshift\_ROP1.0001.cryptomatte.exr?dl=0
Also, below are screen grabs from the masked out results in After Effects. I feel that the difference is pretty drastic. Please let me know what you think.
Once again, thank you for your time!
