Note though that the converter doesn't do any color space correction. (The same for the Photoshop screen shot shown). If you render a diffuse material ball with an RGBtexturenode (1.0 0.5 0.0), and compare the hue to the color you get when you input (1.0 0.5 0.0) into RGB Babelfish , the hue in Babelfish will be much more reddish. Because Octane works in linear space you have to set the RGB color in Octane to (1.0 0.218 0.0) to match the color in Babelfish. So I think you would get better results from tweaking the sliders in Octane than from copying RGB values anyway.
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Roeland
RGB 0 to 255 please!!!!!!!!!
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NOTE: The software in this forum is not %100 reliable, they are development builds and are meant for testing by experienced octane users. If you are a new octane user, we recommend to use the current stable release from the 'Commercial Product News & Releases' forum.
NOTE: The software in this forum is not %100 reliable, they are development builds and are meant for testing by experienced octane users. If you are a new octane user, we recommend to use the current stable release from the 'Commercial Product News & Releases' forum.
- mrjschulte
- Posts: 4
- Joined: Fri Jun 04, 2010 12:34 am
Speaking of which, what is the default primaries and Whitepoint that Octane renders? sRGB primaries and a D65 whitepoint? Something else?
The white point used in Octane is illuminant E (equal energy spectrum). This is slightly different than the D65 white point used for sRGB. Therefore the color balance of the tone mapper is by default slightly off. You can correct this by setting the white balance to (0.758, 0.955, 1.000). The primaries are the same as sRGB.
When loading a texture Octane also uses E, so a floattexture and an RGB color set to (1, 1, 1) denote a flat spectrum. This means that if they are used for reflection values they don't change the color of reflected light. I think this is the expected behavior.
For lights and the environment texture a flat spectrum corresponds to illuminant E, which compared to D65 has a pink tint. A blackbody with a temperature of 6500K is a close approximation to D65.
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Roeland
When loading a texture Octane also uses E, so a floattexture and an RGB color set to (1, 1, 1) denote a flat spectrum. This means that if they are used for reflection values they don't change the color of reflected light. I think this is the expected behavior.
For lights and the environment texture a flat spectrum corresponds to illuminant E, which compared to D65 has a pink tint. A blackbody with a temperature of 6500K is a close approximation to D65.
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Roeland
Hmmm so should we have a small button in the UI or a setting in the options (to go along with the RGB colourspace) that sets the white balance to correct for this being slightly off?
As 0.75, 0.95, 1.0 I mean or is it not that significant in practice?
As 0.75, 0.95, 1.0 I mean or is it not that significant in practice?

i7-3820 @4.3Ghz | 24gb | Win7pro-64
GTS 250 display + 2 x GTX 780 cuda| driver 331.65
Octane v1.55
GTS 250 display + 2 x GTX 780 cuda| driver 331.65
Octane v1.55
- mrjschulte
- Posts: 4
- Joined: Fri Jun 04, 2010 12:34 am
Thanks for the insights Roeland, so we'll assume then that it has equal tristimulus values.
Can we add our own tonemap/colormatrixes/curves to Octane somehow to map to some other colorspaces?
Notable's of interest are DCI-P3 and Rec709 for feature VFX.
J
Can we add our own tonemap/colormatrixes/curves to Octane somehow to map to some other colorspaces?
Notable's of interest are DCI-P3 and Rec709 for feature VFX.
J