OTOY Forums

Hi,

I have one very time-consuming project, which is on a tight deadline and octane is making my life really hard right now.

Scene Setup:

Skycrapers from the Metropolitan Pack and City-Kit by Videocopilot and Greyscale Gorilla. 2K maps with normal maps.
HDR with blue sky and sun.
Sun Object is activated.
Octane v3 newest version.
Importance sampling is on for both the HDR and the sky object.
Normal maps were reduced to 0.05-0-1 Opacity in the image texture node for a more realsitic look.
All materials have a very high index ratio, because the client wants super high glossy mirroring skyscrapers.


Problem:
The reflection of the sun in the buildings is crazy high (super bright) and with the normal maps it produces a lot of flickering noise in the places where the sun is being reflected.

Problem occurs in all kernels but we are using GI_Diffuse for our project.
I tried to inscrease the radius of the sun, it only made it worse. When reducing the sun to 0.1 its a bit better, since its not being reflected over huge areas but only small ones. But if you use any roughness in the materials, no matter how small, the flickering hotpixels are again everywhere.
We tried setting the hotpixel removal to 0.7 but it doesnt help much.

It's definately coming from the Octane Sky Object and not from the HDRis. And there is no way to rebuild the sky object with such parallel lights using octane area lights for example, the look is completely different.
We are rendering with 500 samples, because its enough for most cases and there is not really noise anywhere, expect for the sun's hotpixel.

Is it somehow possible to not have the Sun be reflected AT ALL in reflections? That would solve our probelms INSTANTLY.

I have a project zipped for you guys to look at but because of NDA I can only send it to the devs via wetransfer. Please tell me who I can send it to.

Thanks a lot!

Win10
GTX980Tis
Newest Nvidia drivers.

Hi. You can't hide the sun but you can bake environment and that will solve your problem.
Steps:
1. Live only the sun in your scene
2. create camera in 0,0,0 location and 0,0,0 rotation
3. on camera tag choose panoramic-spherical
4. Choose desired resolution in render settings but it must be in 2 to 1 ratio , i .e 4096x2048px
5. If your sun animated than choose desired frame range
6. Choose render buffer type - float tonemapped (Sun radiance will be clamped to 1)
7. Choose OpenEXR for output
8 . Just render your Sun
9. Use it like HDR environment
Your Sun reflection will be really week and with any roughness on material it will just disappear

P.s. By default the Sun in Octane is 120 times higher than float value of 1 . that's not cool at all