So here is my linear workflow for Mental Ray. Keep in mind that the workflow for Maya-Mental Ray is almost exactly the same. It is my hope that a future Max framebuffer will have a srgb LUT so the gamma utility is not needed.
Mental Ray Linear Workflow from chad smashley on Vimeo.
This entry was written by , posted on April 3, 2009 at 3:47 pm, filed under Uncategorized. Bookmark the permalink. Follow any comments here with the RSS feed for this post.
nice videos, i would never have thought to do gamma corrections
Nice run through. I can imagine how it would be beneficial to have a global setting somewhere in MR that would flip on and off a Color Correction node for all bitmaps/colors in the scene for Gamma Correction; sort of in the same fashion as the Material Override toggle in the Processing Tab. That’s another thing to check into for 2010.
I’m glad that the gamma awareness is spreading.
However, a couple of comments. Max has, since years, had “a global switch to turn on an sRGB frame buffer”.. it’s the Gamma configuration dialog. But yes, it has, in the past, has several bugs and issues. This is what’s fixed in 2010 - we made the darn thing actually work correctly
So from max 2010 onwards, the “most correct” gamma workflow (and should be for ANY renderer) is to
- Customize -> Preferences -> Gamma and LUT Settings
- Enable, set “Gamma” mode
- Set gamma 2.2
- Set input AND output gamma to 2.2 (these are defaults and can be overridden per-texture and per-save later)
- Turn ON “Affect material editor” AND “Affect Color Selectors”
That way *everything* is gamma corrected, including color swatches (meaning, the look of the swatch, the look of the material editor, and the look of the render will match), and since gamma correction and exposure control now applies to the viewport in max 2010, the look of the viewport will *also* match.
This is a much easier and more streamlined workflow than having to glue in “color correction” shaders all over. But you really need 2010 for it to work “correctly” in all places throughout the product.
I plan to blog some on mentalraytips.com about this
/Z
Yes, this method would be preferred if I weren’t rendering to a farm. But if I use this method with a farm, I have to set up each machine individually. So if someone switches a machine back, you have gamma flicker. As of Max 2009 the gamma preferences are not saved with the scene. Although I am told that has changed in 2010, if that is true, I’ll prolly do it this way. Thanks for the comments, keep’em coming!
Max 2010 fixes the issue of the gamma flip with render farms. When a 2010 render node opens a file through Backburner, it will adopt the gamma settings saved in the file. Very handy.
Yah, its a great fix. Now only if Max could recognize that I do not want certain tmaps to be gamma corrected (normal maps, displacements, etc), then it would truly rock.