I recently got one of those thump-my-forehead "duh" moments. The article said my new camera is stupid. All cameras are stupid. They only know one color - 18% gray - regardless of what they cost. It seems that whenever we change our shooting location and the light is different, we need to set the white balance, because the automatic settings in even the most expensive cameras isn't always great. Better cameras have a custom setting that you can change yourself. I just did a series of 5 test shots without anything having been changed in the camera. 5 different rooms, 5 different lighting conditions. Then I did the shots again, holding a piece of white matte photo paper in front of the lens before each shot. The pictures of the white paper show a dramatic difference themselves! Under very bright natural sunlight, the picture of my white paper turned a dark brown. Under fluorescent light, it was dark gray. In 4 of the 5 befores and afters, there wasn't much difference, telling me my camera's automatic setting was doing a good job. In one, however, the difference was quite dramatic! The before shot was very dark, and the after was beautifully bright.
I learned that all TV and movie videographers as well as still camera pros all set their white balance dozens of times as they move to different locations. Special cards are often used - called Gray Cards - for doing this, but many of them just use a simple piece of white paper. I had a difficult time trying to find out where I could buy a gray card. Kodak makes them, but I couldn't find where to buy one. I did find a listing for "Warm Cards" - a whole set for either video, for $65, or digital cameras for $45, and was considering buying them until I tried my little experiment with plain white photo paper! It has to be matte - never glossy, though, I understand.
I had a discussion with a former TV reporter last night about this issue, and she said that her camerman constantly did a white balance before shooting, even if they changed outdoors locations by even a few feet.
I'd love to know if any of you use this technique and what your results are. If you haven't tried it, experiment, and see what happens!
P. S. - My favorite camera is a Canon SD 550. I love it - it's my second Canon. I also have a Nikon Coolpix P1, but will never use it outdoors again because it has no viewfinder - just the LCD screen. Nikons are very consistant with beautiful, bright color, so I expected no problems. Wrong. Here in Florida, extremely bright light is the usual rather than the exception! Camera manufacturers have returned to having both recently because customers complained so much that they can't see the LCD screen in bright sunlight.