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.

Well, that may have answered...

...that question.

The question being, why the hell do photos shot in the Vashon High School gym come out with such wildly different color renditions between two photos shot within fractions of a second from one another?

Example #1 (you'll need to click on the image to see the full details);


And Example #2:



Obviously these two photos were shot within a fraction of a second from one another.

And yes, (Spoiler Alert!) they were shot on Auto White Balance, which may turn out to be half the problem.

But only half.

So while the color cast in photo Number One looks pretty much OK, Number Two (particularly look at the color of the back wall) has a distinctly orangey-pinky cast to it.

W, as they say, TF?

I haven't moved; the gym hasn't moved; so why the hell is the color cast so different (and this is a relatively mild example) between the two photos?

Now, it's a standing joke that the halide lights in the Vashon High School gym are appallingly bad anyway: they're literally different colors, such that you can stand out on the gym floor and almost see no two light of the same visible color.

This is due to age and maintenance, I'd bet: when the individual bulbs have needed replacement I'm sure that no thought whatsoever was given to buying a metal-halide bulb identical to those already installed. Let's get the cheapest, and be done with it.

Add in age (halide lights change color as they get older) and you've got lighting that pretty much sucks.

But why would two photos shot within moments of one another, pointed at identical parts of the gym, have such different color casts?

Turns out the real culprit is alternating current, and the way halide (and fluourescent) lights work.

Halide (and fluorescent) lights are actually cycling on and off at 120 hertz or 120 times per second -- at least those with older non-electronic ballasts -- which I'm sure is what the VHS gym lights are.

Way too fast for the human optic system to see, but not too fast for a camera taking ten shots per second at an exposure of 250th second per.

So apparently what I'm catching here is the actual change in light output/color output of the lights as they cycle on and off at 120 hz.

OK: fine.

What to do about it?

Slowing the shutter speed down to, say, a 60th or a 30th of a second might do it, but that's not going to work for shooting sports.

So I think the strategy is to register a Custom White Balance in my EOS 1D Mark IV and 5D Mark II, and not have the camera think that it's doing it correctly when it's looking at light that's constantly flickering and thinking it's got a valid reading for Auto White Balance.

During RAW conversion and post-processing I just tell BreezeBrowser "This is what color the light is, period" instead of whatever the camera thought it was at the instant a particular photo was shot.

I think.

At least that's the Plan of the Moment(tm).

Seems I should have...

...done more night photography at the Vashon Island Strawberry Festival this year.


These are from Friday night at Ober Park, the Tom Bean Blues band.


Canon EOS 5D Mark II; Canon 70-200mm f2.8L zoom lens at 70mm; Auto-focus one shot; single-center focus point; ISO 6400; Aperture Value exposure; f3.2 at 200th second; Metering Mode center-weighted average; Auto white balance as shot, but RAW conversion with Tungsten white balance.

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.

:-/

Here's a...

...very quick first pick from Varsity girls v West Seattle last night:

This was the first opportunity I had to get the new EOS 5D Mark II into the Vashon High School gym and see what it would do.

I'm very impressed.

First off, having a native ISO of 6400 means that I can set a reasonable manual exposure of 250th second at f5.6, stop action pretty well, and still have something that I can actually see when I'm reviewing photos for RAW conversion and post-processing.

Details:

• EOS 5D Mark II; 70-200mm f2.8L; center spot-point focusing with AI Servo Auto-focus
• White Balance 4000K, for "standard" metal halide lighting; this was kind of a guess since the VHS gym lights are notorious for their weird color due to the random way light bulbs have been replaced over the years, and due to the wildly varying ages of the bulbs themselves
• ISO 6400; manual exposure at 250th second at f5.6; hand-held available light
  
• RAW conversion: Smart Noise Reduction "normal"; White Balance "Color temp" of 4000K; Sharpness "As-shot" of 3; this particular photo had an Exposure Compensation of +0.6
• Post-processing: rotate right 0.5 degree; crop; pull up the low end in Levels to +5

Oh yeah! Varsity won 57-52, and JV won 49-39!

Go Pirates!

Things are getting...

...a little tricky with the RAW conversion for the McMurray girls' soccer photos.

What's going on is that I shot from daytime-no field lights into darkness-full field lights.

The daytime photos were shot White Balance "cloudy" because that's what it was.

The full nighttime photos were shot White Balance 3300K because that's what it was then.

What's happening now is that I'm doing the dusk photos: the final photos of the Varsity match is mostly "daylight" with the field lights just starting to come on, and the first JV match photos were taken as it got darker and darker and the field lights had more and more effect.

So at the moment I'm manually converting the Varsity at 5200K, and manually converting the JV photos at 4500K.

I suspect the Varsity photos will ease toward 4500K at the last of them, and at some point I'll ease down to 3300K as the JV photos move into full darkness.

:-/

Tuesday night's...

...VISC soccer practices gave me a very good opportunity to work on several things I don't usually get to mess with during the course of an actual game.

• A manually-set color temperature of 3300K for the McMurray field lights works about as good as anything's going to get to establish the proper white balance at RAW conversion
• Shot at manual exposure, ISO 6400, 250th second, f5.6, and just let 'er rip: pick up the exposure pieces during RAW conversion and post-processing
  
• alternated between a single center-point-focus and the generic 9 auto-focus points; jury's still out, although I'm still tending to think that the single center-point-focus works best
• alternated between single shot and motor drive; in the past I've found that motor drive doesn't necessarily do any better at catching that One Perfect Moment(tm) than just becoming familiar with a sport and leaving the timing up to my shutter finger

Also I was able to get out on the field, right next to the goal, and get the lights (such as they are) somewhat where I wanted them...

Now up...

Rockbusters Wrestlers 2009, both the wrestler and the team photos..

These came out pretty well, all things considered, that being that they're shot under duress.

Duress being that the coaches want to get this over with as quickly as possible, that I'm working in a small space with 50+ 6- to 11-year-old wrestlers, that there's only enough room for one strobe, and that the floors and lower walls are dark green or a kind of yellow-gold, while the upper walls and the ceilings are yellow-gold (see the Team photos to see what I mean) and the existing lighting are fluorescents that are about nine feet overhead.

Shot with my new EOS 5D Mark II; ISO 200; white balance 5600K to match the single Alien Bees AB800 strobe that was fired into a 60" softbox mounted on a light stand at about chest height; manual exposure at a 60th at f8.0; the strobe is just off my right shoulder and about 10 feet from the subjects for the wrestler shots, and dead-center and back about 18-20 feet for the team shots.

For the wrestler shots the softbox was turned to portrait; for the team shots the softbox was rotated over to landscape and aimed somewhat up at the ceiling.

Now up...

VHS Girls' Soccer v CWA, and Senior's Night 2009:


After re-RAW converting all the second half photos (one of them, above) to a white balance of "Fluorescent" rather than "Auto-As shot" the results are much improved in that they're consistent if not 100% "correct".

I think that if the photos had been originally shot with one specific white balance the outcome would be pretty much spot-on.

EOS 5D; 70-200mm f2.8L with a 1.4x extender for an effective focal length of 98-280mm; shot at 98mm; White Balance Auto-As shot; Manual exposure 200th at f8.0;

RAW conversion: white balance "fluorescent"; exposure compesation +2; PS levels mid 1.1 high 180-200; fill flash 3 lighter, 35 saturation; Neat Image digital noise reduction 5D @ 1600 ISO 200th f5.6; remove only half of noise

White balance redux...

Just decided to re-RAW convert all the second half VHS Girls' Soccer v CWA photos: kept coming across a few photos where the white balance as first RAW converted (from "as shot Auto White Balance") was so weird that the color rendition was just coming outer space.

:-/

The end product should be much improved.

Girls' Soccer Senior's Night 2009 is up at www.finchhaven.com/vhs/ ... /Girls_Soccer_v_CWA_and_Seniors_Night_102709/Seniors_Night

Now up...

Volleyball v Orting and Senior's Night, 2009.

Here's Rachel with another block:


Canon EOS 5D, 70-200mm f2.8L zoom at 70mm; ISO 1600; "fluorescent" pre-set white balance, Available light; Manual exposure, 200th at f8.0; Auto-focus, center point spot with focus lock.

Heavily post-processed: +2 exposure compensation at RAW conversion; Levels: mid 1.1, high 180-200; Fill Flash +3 and Saturation 35; Neat Image noise reduction at EOS 5d, ISO 1600, "remove half of noise"

More on White Balance...

Here's a shot from Pirates-v-Cedar Park that's been RAW converted two different ways:

1) converted as "fluorescent/as shot" or 4000K


and 2) converted as "tungsten" or 3200K in Breeze Browser, which is what I use for RAW conversion.


Fluorescent definitely looks "better" and more "correct".

On White Balance...

Well, the idea that I'd shoot some photos last night at the Cedar Park game (did I mention that the Pirates won, 59-6? No? Well, they did..) while it was "before it was fully dark" turned out to be nonsense. When I got to the high school at 6:30 pm it *was* dark and the only light was the field lights.

Decided to set the white balance at "fluorescent" or 4000K as a compromise/experiment because that's the same color temperature as "standard" metal halide lights, and I figured that having all the photos shot to the same white balance would be better than "Auto" since if fluorescent was off, I could correct duing RAW conversion.

We'll see: I'm burning the *. Cr2 files to DVD right now...

Next up...

VHS Football versus Cedar Park, tonight at 7:00 pm. Right now the long-range doppler radar looks pretty good. Probably wear my full rain suit but no boots. 70-200mm f2.8 zoom with 1.4x extender for 98mm-280mm effective focal length, probably take my Kata rain hood but hope to leave it in the trunk.

Speaking of white balance: I'm going to do a custom white balance after it gets fully dark: shoot a white card, do Menu > Custom WB and select the white card just photographed, exit the Menu, press and set White Balance to the "Custom" icon.

Before it gets fully dark I'm going to set the White Balance at "Daylight" which is 5200K and see how that works.

Metal Halide lamps seem to run in a range from 2300K for "white corrected" (Often used as accent lighting to blend in with fluorescent 2700K applications) to 4000K for "standard" (Used in general lighting; factories: parking lots, warehouses) to 5500K for "Hylux" (Daylight lamps: horticulture, aquariums, high color definition).

Ref: www.venturelighting.com/TechCenter/Lamps/color_of_light.htm

Quickie Tech Note...

Auto White Balance sucks.

A quick hack to overcome some of the bizarre colors rendered by auto white balance in, say, football photos shot at night in available light under metal-halide field lighting is to select a known white area, copy and paste it into a white_sample.tif, and save that.

Then paste the white_sample.tif into a photo that needs a little help, drag it up to a corner, and flatten layers.

Do an Enhance > Adjust Color > Color Cast (or whatever your specific syntax, you get the idea) on the pasted white sample, and voila!

Quick-and-dirty, and it does an amazingly good job most of the time.