Arguably, the early morning and late evening light is magic for photography.
I believe that the color tones present at those times when the light is very soft, and may actually cast a mild pink or yellow cast, should be preserved. The object is to portray the colors exactly as they were seen with they eye at the time. However, often if white balance is not exact (and it's diffiuclt to get it that way unless you set custom white balance) the camera will not accurately reproduce those colors as you saw them.
It's tricky trying to remember exactly how warm the actual scene was, after the fact, and herein lies our challenge. Often it's impossible to be sure that you tweaked the photo just right and that you are presenting the scene exactly as it was in true life.
What I do is try to get the white balance as close as possible, and if I have time, that involves setting custom white balance. But the problem is that the light is always changing, so even that is no guarantee for very long.
I guess the rule of thumb is after you have taken enough photos in that soft light, you get a feel for what looks right. It's also sometimes an eye-opener to compare photos you've just post processed to some you did on a different day in simiilar light, in order to help you judge if the colors are rendered accurately.
This photo below is a good example... taken at Merritt Island National Wildlife Perserve at about 7:40 pm as the sun was setting. I remember the white balance being a little bit off, and needing to adjust if. I believe what I ended up with is accurate, but it's impossible to be absolutely certain.
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