Give user possibility to change white balance relatively
When I change e.g. temperature in white balance section, then save it as a new style and apply it to whole collection then every photo has exactly the same temperature set. It is not very practical solution.
My expectation is:
I change temperature from 4500K to 5000K (+500K). When I save this change as a style and set this style to the image that oryginally had 4700K (from RAW information) I suppose it to have 5200K as a result (+500K as well). This behavior could be optional (relative/absolute change option).
#1 Updated by Roman Lebedev over 1 year ago
- Status changed from New to Incomplete
- % Done changed from 0 to 20
Do note that we store white balance as multipliers.
The displayed Kelvin temperature is not representable (as in, across different software), and is only useful for information.
That being said, i i'm not entirely convinced that this could/should be done.
#2 Updated by Mariusz Jaskółka over 1 year ago
From user point of view:
Maybe this is my opinion but i think it is pointless to set the same white balance to all photos in collection. On the other hand it would be helpfull to make all photos warmer/colder approximetly by the same relative value (na matter which units is being used).
My use-case from today: all collection from the party in room with old-school bulb & all the photos was "too yellow" as my camera was working in auto-white-balance mode. I had to move "temperature" slider left about 500K manually for every single photo.
From programmer point of view:
I understand that temperature value could be calculated by darktable with it's own algorythm and is not compatible with other software. But is it really a problem? Moving slider left/right by the same value from what was read/calculated from RAW manually is possible so doing it automatically with preset/style is technically possible as well. How? One of the solutions could be to switch "white balance" filter between absolute/relative mode (similar to exposure filter's modes). But you are programmers/architects here :) ( I am too but I didn't read the source code ;) )