OTOY Forums

Hi all,

I have an issue that I have been experiencing I think only since Octane 2020. Sometimes my ambient occlusion pass has this weird lighter/darker separation. It looks like it's split in the middle (I also have it sometimes in the render... I think in the latest one, it was split in quarters, not half)


I have the latest version of Octane (2020.1 R5), my studio drivers are up to date. It looks like I have the same issue whether RTX is on or off.

I have 3 graphics card
- 2080
- 2060 Super
- 1080
Plus a 1070 on another computer on my network...

Actually, as I was writing this I wanted to see what happens if I turn off Network Rendering and it looks like it got rid of the problem. Do you think it could be the reason? If it is, is there something in the settings to fix that. If not, then what could be the cause?

Can it be due to using linear color space in render passes? Note that your LV is tonemapped

Hi,
everything is working correctly here with AO pass and Net render: Have you disabled the Minimize net traffic option?

ciao Beppe

Cool thanks, I'll try those...

I have to say that the tonemap thing is still a bit obscure to me.

That clearly didn't do the trick



Now there is the quarter thing I told you about. I'll continue investigating on why it does that, because it's clearly an intermittent thing and I don't think it happens on the full rendered sequence. My money is still on the network render (I unchecked the minimize set traffic option... )

Funny, it actually change quadrant every frame or every other frame like so


For that project it's not such a big deal, I was not really planning on really using AO for the final compositing... And if I need I probably can render an AO sequence from the standard renderer on top (the octane materials I use generate a little of AO, but I can live without it)

I'll look into aoktar's suggestion with the linear color space. The problem is that this issue seems to pop up randomly so reproducing it might be tricky.

muftix wrote:Cool thanks, I'll try those...

I have to say that the tonemap thing is still a bit obscure to me.

Octane can render images in a high dynamic range (for certain formats, such as Octane EXR), which most monitors cannot accurate display without help. That is what tone mapping does. You can apply a tone map both in LiveViewer and in final renders. If you intend to do additional color correction in comp, be sure to choose "Float (Linear)" or "Linear ACES2065-1" in Render Settings, Octane Render option, Main tab Render Buffer Type under the Settings turndown. If you don't want to work further with the image in comp you can choose either "8-bit(deprecated)" or "Float(tonemapped)" in the same location.

Note that these settings will be used to write out the final image that you render, so be sure that you have them set the way you prefer. Make sure that you have set up LiveViewer with the settings that reflect what you intend to render, so that your creative choices using LiveViewer match the results you will get from final render. You can do this via the tone mapping combo box in the LiveViewer.

For further reading on tone mapping you can start here: https://en.wikipedia.org/wiki/Tone_mapping

Cool... If I'm not mistaken, I've setup my render to Float linear, because yeah, it is my plan to do more color correction afterwards. I've recently started to look into the linear workflow... Before that I did a render with a linear color space for compositing on some footage and it did work out pretty well. I'm sure I've made some mistakes and I haven't done everything correctly but it still composite very very well into my shot. Much better than anticipated, but I'm pretty sure it could be even better

Sorry, muftix, we were able to identify and correct the issue with AO pass and Network rendering, and will be part of the next SDK update.
ciao Beppe

Thanks