I have been trying darktable on and off for a couple of years, and I just can’t seem to get the hang of it. I have used GIMP a lot, but darktable just seems to elude me. So, I have a couple of somewhat related questions, to start.
First, how do I do a simple, overall white balance correction? I seem to be getting to the answer in the documentation, but then it goes on to another section, and I still don’t have a “how to do it” answer.
My second question is a bit more complicated, but related. darktable seems to be using info from my camera to set the white balance, but the images seem to be very bright and somewhat blue. But, if I use imagemagick to convert the image to, say, a .png, looking at the .png image in darktable looks just about perfect. I know that imagemagick uses dcraw to read the raw image, and I think it defaults to -4, which is a combination of several options. Anyway, my question is, what exactly is going on? Then, back to the first question, how would I go about getting a similar result with darktable?
Maybe I just need to study harder, but I am trying.
PS - My images are Nikon NEFs from an old D3300. I think it is in the database of cameras darktable has all the info for.
In the darktable view, find the White Balance module. By default it is set to “camera” which uses the white balance value from the raw file. You can move any of the sliders to change the white balance; you should start with the “temperature” slider.
You’re probably also using the Base Curve module, as it is enabled by default. Perhaps the default curve is too strong. You can adjust it. You can control the blueness with the White Balance module.
Different programs calculate white balance differently. darktable is different from RawTherapee which is different from others. You can try the “camera neutral” white balance preset. Overall, it is hard to say what is going on without seeing an image.
Keep asking questions! It’ll all click into place sooner or later
An easy way to do white balance correction is to find something in your photo that is supposed to be plain white or plain grey. Then, go to the white balance module and select “Spot” from the dropdown box. You can then draw a box around the white/grey object in your photo, and Darktable will set the colour of that object to white/grey, cancelling out any colour tint, and adjust the colours through the picture accordingly.
Then, you can use the sliders to fine-tune the white balance for artistic effect (eg. to “warm up” or “cool off” the picture).
I notice also for your camera darktable has some whitebalance presets defined. These try to emulate the whitebalance settings in your camera (eg. sunny, cloudy, etc.). You could also try to use those settings as a base, and tweak the sliders afterward if needed.
White balance information is stored in the RAW file, they are multiplicators for red, green and blue channel.
That’s absolutely OK because the RAW file is (mostuly) unprocessed. It looks dull, unsharp, noisy, not much color and contrast. You have to add this by yourself to get a decent looking image.
When you get a JPG out of a camera, the camera already has processed the RAW file (sharpen, white balance, denoise, add color and so on…) and it looks decent ‘out of the box’
Same for your example with imagemagick. Imagemagick processes the RAW file and exports the result as PNG. That might look better when you open it but you cannot do as much as with the RAW out of it since the PNG already is at least demosaiced and white balanced.
The important part of a RAW developer is what you can make out of it, not how it looks when you open the file. Here is a before-after, the image looks dull at the beginning:
Thanks Tim (I didn’t want to speak on behalf of the admins ).
So I loaded the picture into darktable 3.2, using the default scene-referred/filmic workflow, and I didn’t see a bit problem with the colour balance using the default camera-provided settings in the raw file, around 4700K. I tried doing a spot whitebalance, and got very similar parameters to what the camera provided. When I selected the “Cloudy” preset, the picture looked very warm I thought.
I then wondered if you are using base curve rather than filmic, so I tried selecting the Nikon basecurve, and the picture didn’t look so nice, it was a bit bright and harsh. I’m wondering if that may be what you found objectionable?
@Matt_Maguire , yes, my darktable is using the base curve. I am so new at this, could you give me a quick explanation of how to use your scene-referred/filmic workflow and get rid of the base curve? I would even be satisfied with a pointer to documentation on doing it. Every “new” raw file I open has the case curve already applied.
And @paperdigits, my monitors are not calibrated. I will try to find some docs on doing that.
The gist of it is simply to disable Base Curve module and enable the Filmic RGB module The default filmic preset actually does a decent job for most photos with a reasonable dynamic range.
For more info check out this video: https://youtu.be/zbPj_TqTF88?t=4426 It’s long but informative. The link will take you straight to an example towards the end, but feel free to go back to the beginning if you want all of the theory (maybe later).
About setting defaults: In the preferences section (little wheel top right of the screen) you need to select the processing tab, from there you can set your preference for workflow defaults.
scene-referred - the linear rgb way of doing things,
display referred - the Lab way,
none…
Option 1 auto sets exposure and filmic, option 2 sets base curve. They also set the module order (ignore that for now).
If you are willing to read and watch some linear workflow related material I would recommend the following:
EDIT: Just realized that the above filmic video is for the “old” one. It does explain how it works and the basics, so I would give it a go. This next one is about the latest one:
For those images that already have the base curve applied: You can select all those in lighttable view and select discard history in the history stack module (on the right side). BE AWARE: This will remove all the edits made, not just the base curve!
I would advise you to get a better feeling what it is you want/need from darktable first and start making bigger changes once stuff starts to fall into place for you.
Thank you very much, @Jade_NL . Your first tip is a great help - I thought I was going to have to start each new image, back out the base curve, and apply the filmic module.
I really appreciate the pointers to the docs and tutorials. I need to understand what I’m doing, not just be told what to do.
Here are some samples of what I just did before getting your tips. I think the second one is technically better, but I prefer the first one. I suppose I just like “warmth”.
).
