Physically inacurrate light distribution in Octane

[SSmolak]

This too dark area under "balconies" is not acceptable in modern professional architectural visualizations. Sorry to say.

Increasing ground brightness is not the way because in most of real scenarios, ground is always darker.

But there are three workarounds to make it looks better in Octane - black body emission, additional fake ground invisible to camera with emission and AOV Diffuse Indirect mix with triplanar y- on surfaces. Anyway it should looks better by default.

isn't this most likely "solved" with tone mapping?

Nope because "issue" is only on some parts. It can be done in Photoshop with dodge brush using 32bit image.

I will make new Corona scene with proper Corona material nodes. The last one was not accurate. Also to make sky the same I will use HDRI image instead of build-in generated skies.

[SSmolak]

There are more accurate and near the same scenes. Corona has slight different representation of Hosek-Wilkie Sky mainly color. Left Corona, right Octane.

I think that Octane do it better, more detailed shadowing. Corona is slighty more washed up so I add 1.2 gamma to Octane to make it looks near the same.

I noticed only now that Roughtness doesn't work in Universal Material like it is in Diffuse Material. It works only for specular, metallic or transparent materials. Is that intented ?
Materials like wall looks better in Diffuse Material type and with little roughtness.

[elsksa]

Hi,

Could you please share an Alembic of the scene? For those without a Cinema 4D access/license.

[SSmolak]

Octane Standalone scene included.

Please let me know if this file works fine in Standalone because I have black screen on render output. I don't know that this is Standalone issue or something wrong while exporting from C4D.

[elsksa]

Hi,

Thank you. Unfortunately, it has to be an ORBX since the .ocs project file does require the associated scene files.

I have black screen on render output.

Here is why:

The ACES P3D65 is not intended to be utilized in your case. The only two main ACES ODTs are "ACES.sRGB" and "ACES.Rec709".

The Octane Console log usually display the necessary information when a black frame buffer output is occurring.

[SSmolak]

Thank you for info. Yes it works fine now. Here is updated file.

[noldo]

Try this.
You can boost the "fill light" effect raising the emission power.

[SSmolak]

Probably you sent wrong file. There is no Emission anywhere on materials and light. I had temporary scene with fake unvisible ground and emission turned on that works great for additional fill light.

[elsksa]

Hi SSmolak, thank you for the ORBX!

First, I'd like to point out that using emission is absolutely unnecessary and is non-sense. More than a decade ago, and in real-time game-engine, it would have helped but not in an advanced offline light transportation renderer like Octane.

I've slightly modified the provided scene. I have basically:
1. Boosted the sun values to higher, resulting in more light energy in the scene, which is common in feature film/animation. No one should be afraid to push these values as long as there is an active reliable display rendering transform https://skientia.co/cgi/rendering-transform.
2. Lowered the Camera Imager's Exposure value.
When exporting to EXR, the Camera Image parameters will not be baked to it. Therefore, the same will have to easily be done in post.
3. White-ish value on the Glossy Material is .5, a bit of roughness, a bit of round edges (preferably done at modeling level), lowered the specular value (default is 1).

I'm using Filmic OCIO (AgX supersedes it now). No need for the unreliable, unnecessary and inappropriate ACES.
All of it is similar to photography, without being "scientifically accurate" as it is pointless to go down this path on a user-friendly light transportation PT offline renderer.

GIF file:

It will likely have to be opened in a new window, as I do not think the forum allows to automatically "play" the looping gif files. Live Render View froim Octane Standalone.

Does it meet your expectations?

[SSmolak]

Thank you very much Elsksa for that ! It looks very interesting. I will check this more deeply soon.