Shader picker colors versus rendered results

Started by billg60, April 15, 2010, 01:21:23 am

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billg60

I am trying to match shader colors to images I have of my subject area but I have been frustrated by the resulting colors in the screen renders. They always seem to end up lighter. I am using default renderer gamma of 2.2 which I suspect is the source of my confusion. To epxress more clearly what I am trying to understand, I added a constant shader to my network and selected full red (255,0,0). The rendered image ends up with the color red not brighter than (241,64,99) which was a dull bright pink. Setting gamma to 1 brings the rendered colors near the original input color. This basically mirrors my experience with more normal natural colors. How can I specify colors from real world images and obtain similar colors in the renders.

Thanks for the help
Bill

Oshyan

Color picking is a tough thing because it's not just gamma that affects it but also lighting and atmosphere. Your light strength and color in particular have a large effect on non-luminous and non-specular surfaces, especially when close to the camera. At further distances atmosphere also has a large impact. The best thing to do I think is to determine your preferred destination gamma then pick colors by their RGB values (if you know the colors you want by those values) and trust the program that it's rendering the right colors. If it doesn't look right, you can generally assume then that the reason is not in the selected color but in the environmental conditions, and tweak accordingly.

Of course a rendered image showing the problem would always help further inform any discussion.

- Oshyan

Henry Blewer

I sometimes need to adjust the colors when I get the atmosphere settings how I want them. Oshyan is right about choosing colors. After a couple of renders it gets much easier to pick colors.
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TheBlackHole

Terragen uses linear color space, not RGB-Gamma for surface colors.  Darken your sampled colors until they look right.
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