How does the human vision system perceive color, and how can/should this be taken into account when taking and post-processing photographs (both in color and in black and white)?
The bit above is the question I'm asking; below are some follow-on musings exploring some of the question-space.
How do the color receptors in our eyes relate to the RGB used in Bayer (and Foveon) sensors and in RGB color spaces? Do the R, G, and B primary filters used correspond directly to the different types of cone cells in the retina? If not, why not?
How is the color response of the eye interpreted in the brain? How do those three (overlapping!) wavelength-responses get translated into a full range of hues?
Are there certain areas within the color space which we perceive where we can distinguish more close-together gradients of color? Are there areas where we effectively have "blind spots" within the spectrum — areas of low discrimination even though the wavelengths of light vary significantly? How do film and camera sensors respond in these same areas, and are there pitfalls or features which can be exploited due to this?
How much does physiological color perception (the specificity of discrimination mentioned above, in particular) vary from person to person? Leaving aside color blindness, are our cone cells all tuned to exactly the same frequency? How important are differences in this area to overall color perception?
What is the mechanism by which our internal "auto white balance" works? (Is it based on learned knowledge about the way things should look, or is physiological?)
When we look at a black and white image, how does our memory of color affect our interpretation?
I am aware of and have read the Wikipedia article on human vision and on cone cells and some of the related articles one gets from following the wiki links. A summary of the basics is fine in the answers, but I'm really looking for aspects that are interesting for photography.
D. Lambert adds in a comment to an answer below:
Ok, so this is a pretty good biological introduction, but how do we, as photographers, make use of this info? Do we boost blues in our photos to compensate for low "S" counts? Is there something we should be doing to take advantage of the extra sensitivity for greens? Maybe there's something about the way our brains process color that accounts for the appeal of B&W photos in some cases. Is anyone aware of any work in this direction?
which is exactly the sort of thing I'm trying to get at with this question.
I found this quote to be interesting:
Our brains generate the colors we see for reasons of biological advantage, just as brains make up the qualities of all our other perceptions. If you have doubts about this assertion, consider the perception of pain. The sensation we perceive when we accidentally touch a hot stove is not a feature of the world but a sensory quality that leads to useful behavior. — Dale Purves, Brains: How they seem to work, FT Press, 2010
When we take a color photograph, we are working with that sensory quality in a unique way, different from how a sculptor or even a painter works. How can awareness of this be used in creation or appreciation of photographs?
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