There is an immediate answer...

...to the weird lighting in the Vashon High School gym issue.

That issue was the apparent fact that at a shutter speed of 250th sec and up it's quite possible to capture the changing light output/light color as the metal halide gym lights cycle on-and-off-and-on at 120 hz or 120 times a second.

Consider the following, as-shot:



ISO 12,800, 400th second at f5.0, Auto White Balance.

Not bad, really, and maybe some snapshot-shooters would be satisfied, but to me it's way, way too cool and bluish.

(I've been researching the detailed EXIF data for Canon EOS 1D Mark IV RAW files, and I have yet to figure out just exactly how Canon encodes the white balance data for a photo shot on "Auto White Balance". It's got to be in there somewhere, but currently I'm thinking it's not expressed in degrees Kelvin but rather in an RGGB quadruplet, which I have yet to find/decypher).

Merely doing the RAW conversion with the White Balance set to Fluorescent (approximately 4000 degrees K) improves the photo quite a bit:



except that now it's too yellow-y and the skin tones are too flat.

So, clicking on "More settings" brings up the "Additional Settings" (!) dialog, where we can fiddle with all sort of stuff.

We've got a Blue B9 ... B3 ... 0 ... A3 ... A9 Amber slider, a Green G9 ... 0 ... M9 Magenta slider, and a "Color Tone" drop-down -- which is actually Reddish skin tone -4 ... 0/as-shot ... +4 Yellowish skin tone range -- to play with.

Remember since we're talking about light, we're talking Additive Color here.

Take a look at the Additive Color wheel and green is opposite magenta (which is the combination of red and blue) while blue is opposite yellow ("amber" here) -- yellow being red and green combined.

Which is why our pairings here are "blue" to "amber" and "green" to "magenta".

Why "skin tone" rather than a "red" to "cyan" pairing? I'd guess that a lot of real-world photography has a greater need of fiddling with skin tone rather than fiddling with colors ranging from red to cyan. Also, "skin tone" is a specific adjustment in the Canon EOS Picture Style system, which is what we're really doing here: making micro-adjustments to Canon RAW files before we convert them to tiffs.

Anyhoo, when I pull over the Blue to B5, and dropped down the Skin Tone to -4 Reddish, I get something that I like better, at least, than any other setting.

The floor particularly has lost a little yellow, the skin tones look a little more alive, the green of the uniforms seems to have a little more pop, and we're good to go.

(Note that despite all the sliders and pull-down dialogs this all ends up being really subjective, and also implies a calibrated monitor, which I have).



Here's the finished product:



So to correct the weird lighting issues from the volleyball match I shot in the Vashon High School gym I ended up fiddling with the Blue-Amber slider particularly, added in a touch of Magenta on a couple, and pulled up or down the Skin Tone a taste on a few.

And they came out OK, at least as OK as I was willing to spend time with them.

The real test will be photographing the next VHS volleyball match this coming Friday.

It is absolutely astonishing...

...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.

:-/