Postby mdavis » Wed Dec 12, 2007 1:56 am
I guess it really depends on the image. I shoot a lot of landscape stuff, some old barns, old cars, stuff like that. Often, there really isn't a "good" highlight to be found unless you compress the histogram down to force one toward the top of the range. Reflections don't work and can be dangerous since there is usually no information in them, just blown out light. So for my work (and everyone's mileage may vary), I often find it very tough to find a true highlight, a true neutral. I like to use shaded white if I can find it (snow fields in the mountains if they don't have that red algae in them), or a shirt collar on the down-lit side, a white painted building on the shady side, etc. A neutral pin doesn't have to be 126,126,126, rather it can be anything that is neutral, light or dark. Concrete is usually safe, rocks, especially in the mountains, can be very misleading and colorful, not just reddish. Tires are good.
There is a very interesting and informative (and eye-opening) lesson in Dan Margulis' book "Professional Photoshop" in an earlier version (not the current 5th edition) of a man in a gray suit. I haven't had time to work through the 5th Edition yet but I'm sure there is a replacement for that image in the latest edition as well. The bottom line is that, if you put a marker on various locations where you "should" know what a reasonable color balance is, and you pin something that looks like the right pin but the color balance goes haywire (becomes unreasonable) elsewhere in the image, then you have guessed wrongly.
My experience is that, if you use pins, be very critical afterwards that the pin hasn't thrown the color balance off for the remainder of the image. And of course, you have to decide if you want accurate colors, or impressive images that exploit saturation moves.
Thanks, Greg, for standing in while Mike is off flying around!