...how fantastic the output of the human optical system is, compared to the output of even a moderately high-end digital camera.
If you were to walk into the Chautauqua gym for a basketball game, the lighting would look perfectly fine to your eye: whites are white, skin is skin, everything's in it's proper color.
But to (even) a Canon EOS 5D Mark II, it's dark, and the lighting (some sort of halide lights) is some *really* weird color.
All of the following were shot at ISO 6400, manual exposure of 250th second at f5.6: my standard "indoor sports" setup. Working from past experience at the VHS gym, white balance was set to 4000K or "fluorescent".
Example 1: RAW converted with a white balance "As-shot fluorescent" (4000K) and with an exposure compensation of +1.6 which yields a nice, fat, well-centered histogram with just a tiny spike of data off the right end, which I don't care about since it's blown highlights that don't even end up in the cropped image:
This is just *way* too pinky-rosey-yellowy, or something. It's just not right.
Example 2: RAW converted with a manually-set white balance of "Color Temp" at 3300K (this after some experimentation) and with an exposure compensation of +1.6 also...
This one's better, but still too yellow to my eye, and the actual colors in that gym (the key, the back wall) are just not what I remember them to be.
Example 3: RAW converted, again, with a manually-set white balance of "Color Temp" at 3300K and with an exposure compensation of +1.6, but now color corrected in the tiff within Photoshop, this by manually selecting an area of white jersey in shadow (aka "faux" 18% gray) and clicking to define "white" for this image specifically
To my eye it's this last photo that's "correct", or maybe "more" or "most" correct. The whites finally look really white and all the other colors (the gray-green of the key is a good example, the wall in the background, the flesh tones in the shooter's left arm) are reasonably close to spot-on.
And the human optic system does all this correction on the fly, in real time, with out having to be told, and without us even thinking (or, for that matter, knowing) about it.
:-/
