Today’s Question: When you’re in a tricky outdoor white balance situation, do you use any special tools to determine white balance or do you just set your camera and try to make adjustments in post processing? I’m often not sure I’ve gotten it right in post.
Tim’s Quick Answer: You could use a custom white balance setting in the camera to ensure you are starting with color that is as close as possible to the actual lighting conditions, evaluating the results in the camera with a comparison to the scene before you.
More Detail: I typically use the “Auto” white balance setting in conjunction with raw capture, since it is then possible to fine-tune the color when processing the raw capture with no penalty in terms of image quality. That’s because the white balance setting is really just a metadata value and does not actually change the raw image data captured by the camera.
However, if you’re trying to ensure the colors are as accurate as possible, the Auto white balance setting is not necessarily the best option, as you would then need to make adjustments to the color in post-processing based on your memory of the scene.
To help ensure you’re getting a photo with the most accurate color at the time of capture, you could set a custom Kelvin value for the white balance on your camera. You could evaluate the setting with the Live View display, comparing it against the scene before you, or you could capture a test photo to compare to the scene. You could still fine-tune the color in post-processing, but you would be starting out with a photo that has more accurate color based on the lighting conditions of the scene you were photographing.
If you were dealing with a situation where you want the colors to be truly accurate, as though the scene were illuminated by perfectly white light without any color cast, you could use a custom white balance setting in the camera that involves capturing a reference image of a neutral object such as a blank sheet of paper or gray card. You could also use a more sophisticated approach such as using an X-Rite ColorChecker Passport (https://bhpho.to/3aXUlVx).