Is there a way to reverse engineer white balance in RT?


(Stampede) #1

Aside from photography, I build a lot of sculptures and devices that incorporate burning propane. When I take pictures of people near the flames, the color of the light on their skin is really nice. Sometimes, though, my camera’s AWB does too good a job, and turns the fire from orange-yellow, to white.

I see that RT has a “camera” setting where you choose what WB to use. Is there any way to look at a picture where I really like the color, use that as a reference, then get the actual K, tint, Blue/Red and AWB temperature bias numbers, then save them as a custom white balance for the times when the camera gets it wrong? Even better, I’d like to set up a white balance profile in my cameras, because it is an unusual lighting situation that is far from “stock” but I shoot in it often so I’d like to make a shortcut in camera if I can.


#2

RT is well-documented. See http://rawpedia.rawtherapee.com/Main_Page and search this forum for answers.

As for making camera settings, I tend to choose a preset and stick with it in similar shots. Depending on how your camera’s metering works, AWB can be wildly unpredictable. It is better to have a known and consistent WB for adjustment and batch purposes in post. Once you find your ideal preset, you will still have to modify the WB, etc. settings in RT but it won’t take you as long.

When fire turns to white without detail, it means that you have overexposed the shot. It is possible to recover it in post but maybe you need to reconsider the composition of your shot.

PS It would help if you gave us a sample. :wink:


(Mica) #3

I think the real question is, are their any other types of lights besides the flames in the shot? If yes, then color balance becomes more of a pain. If not, then finding the right balance should be relatively easy.


(Shreedhar Inamdar) #4

RT has a dropper to select the white balance. In your situation, I will use it in the following way: Find an object which you know to be close to the opposite color of the flame in the color wheel (blue for yellow etc). With opposite color light falling on it, it should become white. Right? So use the dropper on that object to set your white balance.