H19 OCIO/ACES setup Tweet

[mirocreative]

Hey Everyone,

just updated to Octane 2021 and H19, but can't really set up OCIO/ACES for EXR output. Worked fine in H18, but can't get it working in H19. Anything other than PNG saved with messed up color space and look - even Linear EXR files show up funky looking.

I'd be really happy if anyone could shine some light on the setup.

Thanks!

[juanjgon]

H18.5 and H19.0 should have the same workflow. The only difference is the H19.0 supports OCIO 2.0 itself, making the things easier while working with these OCIO configs. Perhaps you could check this topic, and this article:
viewtopic.php?f=101&t=78579
https://www.elsksa.me/scientia/cgi-offl ... rvival-kit

Thanks,
-Juanjo

[mirocreative]

Thanks, will check the links, trying to use the previous workflow, but it doesn't work. As soon as I change color space, colors are messed up - it seems like a gamma issue.

There's one thing I might have missed, 2021.1.0.4 is Python 3 or one version back?

[juanjgon]

The plugin should work in both versions, although the H19.0 plugin build has been compiled against the python3 version, which is now the default one.

Thanks,
-Juanjo

[mirocreative]

Great, so that's not the issue, using Python 3 version of Houdini. I'll keep on trying

[elsksa]

Hello,

There seems to be a lot of confusions resulting in some uncertainty.
I will share below, links that will help clarify everything:

OTOY Forum thread replies:
https://render.otoy.com/forum/viewtopic.php?f=34&t=77680&p=404154#p404154
https://render.otoy.com/forum/viewtopic.php?f=30&t=77601&p=404147#p404147
https://render.otoy.com/forum/viewtopic.php?f=30&t=77601&p=404534#p404534
https://render.otoy.com/forum/viewtopic.php?f=30&t=77601&p=404596#p404596

My informative pages:
https://www.elsksa.me/scientia/cgi-offline-rendering/digital-imaging-survival-kit
https://www.elsksa.me/scientia/digital-imaging/linear
https://www.elsksa.me/scientia/cgi-offline-rendering/rendering-transform
https://www.elsksa.me/scientia/cgi-offline-rendering/octane-render-color-management
https://www.elsksa.me/scientia/cgi-offline-rendering/octane-render-aces

Trying is hit or miss. If the correct steps are followed and executed, there should not be any problem.

Additionally, a lot of individuals are using ACES while not being aware of how inappropriate and overkill it is (in most cases and again, for most individuals with little to none digital imaging background). The links above contain most of the important information for a proper color pipeline chain by explaining the fundamentals and showing different ways (via EXR, via TIFF, so it does fit the workflow of various scenarios without being overkill or breaking the imagery, to some extent).

[mirocreative]

Great, thanks for the help! I'm more or less have a basic knowledge of ACES and I was sure it's a technical issue - turned out I was right, it's a view transform node glitch. I'm glad I kept on trying

Not sure what's causing the issue, but when I set up color spaces to ACES, it breaks the OCIO view node and I have to select any other view transform than sRGB, then select sRGB again. Works like a charm

Appreciate your help!

[juanjgon]

Not sure what's causing the issue, but when I set up color spaces to ACES, it breaks the OCIO view node and I have to select any other view transform than sRGB, then select sRGB again. Works like a charm

This can be a limitation of the render target HDA. Without selecting a display name (even if it's the default one) the HDA can't populate the view names drop-down menu. I've not found how to resolve something like that yet.

Thanks,
-Juanjo

[mirocreative]

This can be a limitation of the render target HDA. Without selecting a display name (even if it's the default one) the HDA can't populate the view names drop-down menu. I've not found how to resolve something like that yet.

Sure, no worries. Now that I'm aware of the glitch, it's all working great.

[vurt]

Hi,
I've run into problems once enabled OCIO in H19.
Before it was working great without it, with selecting ACEScg as the color space. Once enabled OCIO in Houdini color settings (via houdini.env) I have following:
When I keep using ACEScg as color space, 1: it looks dark in IPR (like ipr doesn't support aces suddenly). 2: I have an error of the ROP: unable to evaluate expression ... ROP/HO_img_ocioColorSpace.
If I select OCIO as the color space, no matter which OCIO space role I select, the IPR is dark.

If I disable OCIO in Houdini.env, and I see that the viewport doesn't have ACES and no OCIO options in ROP, I still get that ROP error with the expression.

Also, this ocio space role (HO_img_ocioColorSpace) always comes blue, has expression/channel on it. Might that be an issue?

So basically I can't render anything, with or without OCIO now, please help ASAP.

Using Enterprise build of 2021.1.1.0 rev2 with the hair fix by Juanjo.

*edit* removing the channel reference solves the error, but still the workflow if cumbersome. OCIO as colorspace renders black in IPR. ACEScg as colorspace looks wrong in ipr. So while working I have to turn on sRGB, and by render out have to switch to ACEScg. At least it works.

Thank you,
D