Color issues after 3.4 update.

[jgriffin]

I updated all of the machines in the studio to 3.4 a few weeks ago and we've been having an interesting issue in which some machines, when rendering as part of the render farm, are gamma correcting the final output. (Darker images are incorrect)...

https://dl.dropboxusercontent.com/u/...5_010_v008.mp4

The above movie is of a Render Layer with surface shaders applied to the geometry, there are no v-ray render elements but it also appears in a more typical beauty render. Render Element outputs are unaffected.

This only seems to happen on scenes that were originally created using v-ray 3.3. New scenes are rendering correctly so far.

The machines doing this are artist workstations that are added to the render farm after hours. Dedicated farm machines render correctly.

I have reinstalled 3.4 a couple of times now, checking the "remove previous version" option.

Also, the same machines which are darkening final renders will not render (or at least will only write a black image) a Render Elements specular pass.

All machines are MacOS 10.10.5, Maya 2016 SP6 and V-Ray 3.40.03.


I'm thinking there's a preference that artists have set somewhere for version 3.3 that is now misbehaving in 3.4 but I'm not sure where that might be. The render globals settings are consistent across new and old scenes, linear workflow settings are correct and the vraySettings.xml in maya2016/vray/conf has only one entry: "<RenderSwatches>1</RenderSwatches>"

Any ideas what's going on here?

Thanks!

- J

[Mihail.Djurev]

Could you check if the Color Management settings in the Maya preferences differ from the defaults?

[jgriffin]

Here's the color management panel.


The artist working on this problem shot said that he had some v-ray frame buffer adjustments on and when he turned them all off, the colors rendered fine across the farm and other workstations (the specular pass issue persists though). I didn't think VFB settings had any affect on final rendering but I've been wrong before.

Thanks!

- J

[t.petrov]

Are you saving exr/vrimg files or are you saving png/jpegs/etc?

[jgriffin]

Always EXR.

[yolov]

With what version of V-Ray was the scene saved/made?
Is there a chance that one of those machines uses a different version?
Do you have the same problem if the you disable Maya's Color Management?
If you get a correct render of the specular render element on other machines - can you check if versions differ between the machines that render it correctly and the ones that don't? Also can you share the scene where the specular channel is not rendered?

[jgriffin]

I finally had time to dig into this and it's all user error. The script I was using to install v-ray on the studio machines was reporting a successful install but not actually running the installer.... clearly I need more Bash experience. All machines are finally updated to 3.4 and all renders are consistent and beautiful again.

Thanks!