[quote author=Ibn link=topic=5876.msg73996#msg73996 date=1231786280]
How close are those colors to the real deal? I'm just wondering why you didn't do a custom white balance (white bal card in tank...)?
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I think they're pretty close. On my monitor at home the images look fairly similar to the tank itself. There's probably some shift but it's the same shift in all images, so while the absolute color may not be quite perfect the difference in color between bulbs is accurate.
I didn't do a custom white balance using a reference in the tank because that would compensate for the color temperature of the bulbs, which is much of what I'm trying to compare. Our perception of color temperature works a lot like tinted glasses: if you put on glasses with green lenses, after a bit things don't really look green anymore. That's the point of a camera's white balance adjustment: to compensate for our perceptual adjustment to different lighting conditions.
When we look at a tank our eyes aren't adjusted to the lighting conditions of the tank, but rather the lighting conditions of the room the tank is in. I could have done a custom white balance using a white card in my living room, but I didn't want these images to be dependent on my living room's lighting conditions. I also wanted the images on a monitor in my living room to match the way the tank looks in my living room, so using the monitor's white balance is appropriate.