Rebuilding tonemapped live viewer in AOV system

[Tim_Twisted]

Hi,

I'm trying to recreate the exact image from my live viewer through the AOV system, but there seems to be something I'm missing as the colour/gamma is slightly off. It would be great if anyone can take a look and let me know what I'm doing wrong.

I'm also wondering why some of the values used in for instance bloom differ from the ones used in the post effects from the live viewer? Post processing uses (decimal) numbers whereas the AOV uses %, and vice versa for spread which makes it difficult to copy. It would be great if an AOV node named "Image Processing" could be added, with the exact same options as the one in the Octane Settings.

-Tim


Octane 2026.2 - 1.8.3
Cinema4D 2026.1

[bepeg4d]

Hi Tim,

The issue is caused by the order in which is applied the "Apply Gamma curve" node AOV.

If you go to the Imager node, and change the order from "Response-Gamma-LUT" to "Gamma-Response-LUT" then also change the order of the AOVs, applying firstly the Gamma and then the Response correction, the result is the same:

So, to have the same order and result, you need to apply a couple of Color conversions:
- from Liner sRGB to sRGB, before applying the Gamma correction
- and from sRGB back to to Linear sRGB after the Gamma correction:

Here is the modified scene:

AOV_Tonemap_b.zip

(128.38 KiB) Downloaded 8 times

ciao,
Beppe

[Tim_Twisted]

Thanks Bepe,

Quite a logical solution now that you explain it. The AOV system feels quite underused by many, including myself, but with intricacies like these and the lack of documentation is a big hurdle to really start using the system in more advanced ways.

[bepeg4d]

Hi Tim,

I'm with you, Output compositor has become too much complex to use, but we are working on both plugin and Standalone side to make it more user friendly.

Stay tuned!

ciao,
Beppe