OTOY Forums

Hello everyone.

Well, i bought Octane and i've learned that i am not a tech genius. Im a simple artist. I've gone through the online documentation and the otoy youtube videos. They are great for a general understanding. But once i start to apply what i've learned, certain issues start to arise.

The biggest issue is Gamma control. Yeah, im aware of the post on the boards about gamma. I understand the concept as i've worked in photoshop professionally for years. The issue comes in when your trying to set up multiple settings with the correct gamma. Especially in regards to HDRIs. Typically, I will work with the C4d plugin as follows:

1. Go to the octane settings tab and select "Linear" as the space
2. Set the gamma to 1
3. Go to C4D project tab and make sure i have the "Linear" work flow option checked
4. In the C4d project tab I make sure that the color profile is set to "Embedded" for imported images
5. Create an octane environment object and click on the button that allows me to load my HDRI
6. Once the HDRI is loaded, i click on the thumbnail image to bring up the color profile settings and i choose "Linear"
7. Any images i load into materials i make sure that the gamma is set to 2.2 and that either "Embedded" or "SRGB" is set for the color space.

But after all this, the tonal range is still all jacked up. any tutorials that covers the linear work flow process from start to finish? It seems i've covered all the steps but the results are horrible. Only sometimes can i get a decent image and I cant find a good comprehensive tutorial series on Octane. Hellolux has a basic one but this is beyond that.

Thanks in advance.

I did a test so you guys can see whats happening.

The first image is of my scene rendered in C4D + Octane
1. Please note the Octane settings on the left. Linear is selected and i am using a gamma of 1
2. Also, note in the lower right, the HDRI has its profile set to "Linear"

See how dark the image is? And if i adjust the gamma or exposure to try and brighten it up, that doesnt help. Its the tonal range thats all messed up.



The second uploaded image:
This image shows the scene on the left rendered in physical. This is my standard linear work flow with Physical Render. Perfect, nothing unexpected. Now look at the messed up tonal range on the right...thats in octane.

Heres the second image i was refering to

I guess i figured it out. For some reason in the Octane settings, the gamma needs to be set at 2.2 for a Linear workflow. This is odd, i always read that in a linear workflow your gamma should be set to 1.0. But as you can see, now that i switched the gamma from 1.0 to 2.2, it matches the Physical Render image in my first post.

I will post back if i run into any hurdles with this issue. Im going to test more HDRs.

Glad you kind of solved your problem! Nevertheless you should always try to use Octane ImageTexture node instead of C4D's Bitmap Shader - in your materials as well as for your HDRs.
Not sure if this solves your problem but i saw you were using C4D bitmap shaders in your screenshots and i read using ImageTexture nodes can prevent you from certain different inaccuracies.

Have a good one!

jopfe wrote:Glad you kind of solved your problem! Nevertheless you should always try to use Octane ImageTexture node instead of C4D's Bitmap Shader - in your materials as well as for your HDRs.
Not sure if this solves your problem but i saw you were using C4D bitmap shaders in your screenshots and i read using ImageTexture nodes can prevent you from certain different inaccuracies.

Have a good one!

Hi jopfe. Thank you for taking the time to respond. I actually have two sets. One is a set of C4D for the Physical Render test and one set of Octane materials for the Octane test.

aoktar wrote:https://www.facebook.com/groups/OctaneRender/permalink/809669179210162/

Thank you aoktar. I requested to join the group. Hopefully they will accept the request soon.

Best regards,
Robert.