A lot of people use a "gray card". I don't. I don't care if the white balance is "correct", I care if it looks good. I'll often make a portrait warmer or a food photo cooler. I also shoot in raw, which allows me to adjust the white balance in post without data loss. If you don't shoot in Raw and you're a photographer you should.. but that's a whole other post for another day.
Take this photo I took for example of Yellowstone Lake at Yellowstone National Park.
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It's pretty, warm, cozy and energetic. The oranges in the sunset are beautiful.
But what if I changed the white balance...
Take this photo. Same scene, same time of day with a different white balance.
In this case, one is not better than the other. They just have different feels and different moods to them.
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The colors here feel relaxing, cool, crisp. This is the same photo essentially but with a different white balance to create completely different effects.
Most photos will not work like this however, but the really great, well lit photos will. And one more little tip, as a last resort, if your colors really really aren't working, because you have multiple light sources that are different color temperatures or etc... just make it black and white. A black and white post is coming soon. :)
-Jonny Carroll
Photographer
DTX photography
Dallas Aerial Photography
Denton Wedding Photography
Little Elm Photography
Dallas Commercial photography