Somehow, I managed to set my camera white balance to “flash” so I now have a stack of outdoor photos with the same Color Calibration default:
CAT16
CCT: 5007 K
Planckian Black Body
Can I correct this in DT, for example by applying the Color Calibration option "detect from image surfaces?
How do they look?? CC has assigned them to be a good fit to the curve… maybe share one that is a throw away but demonstrates your wb issue…I don’t think this will affect the raw file processing by CC module…
ER6_8922.CR3 (9.3 MB)
CC-0 rights as usual
In truth the images are not that bad, except maybe the ones shot just after dawn.
Here is a quick process of the image, using the eye dropper in Color Calibration to take WB from the bird’s white neck feathers:
Here the CCT comes in at 3899 K and the sky is blue.
NB I uploaded the wrong CR3 and have now corrected this.
as shot and flash applied to the raw were essentially identical when selecting using legacy WB… and using CC approach using default calculated setting or setting it to as shot really didn’t make much difference… So from the perspective of a default starting point…doesn’t seem to be a big deal…
What worried me was that every shot got the same Color Calibration settings - regardless of time of day, or whether shooting a bird in deep shadow.
I know this isn’t darktable, but I think teasing out the operations has merit…
First, this is “as-shot” white balance:
It’s really not bad, just a little warm if you pixel-peep the white feathers. So, I took a patch from the bottom bird’s white-est feathers:
Truly white feathers and a more interesting sky color, with a slight adjustment like this (multipliers generated from the patch):
whitebalance:0.858,1.000,1.200
I hope I am not missing something here, but I opened the image and the easiest solution for me was to disable the color calibration module and just use the legacy white balance module and set it to daylight. This could be created as a style for processing all the shots to get the starting point you like. Also you could copy these settings from one image and paste the setting into a large number of images in a single copy and paste action.
You may well be right, but I am wondering if Color Calibration does other desirable things besides setting a good white balance.
It sets white balance in a more sophisticated way, trying to take the non-linearities human perception into account. The white balance module just multiplies the input with a diagonal matrix (applies multipliers to red and blue, leaves green alone).
Just like for white balance, it is possible to pick a spot for white balance in color calibration, too, and then copy that to all images sharing the same lighting conditions.
As @kofa mentions it takes or attempt to take into account our perceptual relationship with color.
That doesn’t mean it will always succeed or be better. The case in point are those cameras that don’t have good reference values will often end up with skewed color and so tweaking and confirming those base values is key to successfully applying the CC. Also after some reading there are also instances where color accuracy can be negatively impacted by the perceptual correction. So its another perhaps more sophisticated approach but like all manipulations there can be caveats and trade offs…
The general explanation of this approach is fairly well described here. Section 5 explains the application of it for the purposes of white balancing… Yuhao Zhu
I too previously asked the very same question. The main advantage of the CC module in my opinion is that it can be applied as multiple instances if you have mixed lighting conditions. The other big advantage is that it has spot color mapping which allows you to measure a color in one image and match that color in another image. Besides that, I feel there are times when the simplest road is the best road and in the case you present that would be legacy WB. BTW, great shot of the birds.
