That was the kind of questioning that I appreciate. Those were the right questions to ask, and you demonstrated for yourself what I often see. I use the "stubbornness" of colors like that blue as a sort of intuitive gauge of correctness--if I can't make them go away, they're probably real and not processing artifacts.
Somewhat real, anyway. I could believe that the blue isn't quite so vivid, and if you use TrueColor(natural) as the model, you probably would see a much duller blue because of the heavy suppression of green and blue in the mixture. Also, my choice of filter channel I use for brightness makes a difference. That image used the average of L2,5, and 6; if I'd used L2, for example, the blue would be much dimmer, and conversely if I'd used L6 it would be brighter. The more channels I use the better, I think, because that more closely parallels (and inverts) what happened in the autoexposure sensor in the camera.
I still don't know the precise value of that blue, but I do think I'm closer than I was last week. I'm still working on refining the model.
Space/Science » in reply to On second thought....
re: On second thought....
The whole thread (33 posts)
- Glassy material at the Spirit site.
- Mazatlal rock--MI and color
- Clarification
- some guesses and first impressions
- 3D image of the glassy material.