What does it mean “the new D65 values”?
- If you have a monitor calibrated to D65
- then you can take a picture of it
- and extract the correct multipliers that you should use instead of the one shipped with darktable. You would use those (as a preset of the white balance module) instead of camera reference, along with color calibration. You’d get a warning about double white balance, but that can be disabled in preferences.
See the first link in White (dis)balance and Darktable - #47 by sgotti.
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Ah, thanks. Well, I don’t have my monitor calibrated. I’m a hobbyist, and nobody would care.
Another thing to set workarounds for.
Then try your phone or tablet, especially if it’s an Apple device. They usually have pretty good displays that are factory-calibrated.
I use an older Eizo. It’s told to be calibrated pretty good, I wouldn’t bet on it though. 
To me it seems quite an user unfriendly solution in general. For most cases what I’d have achieved with this is that it would finally work as it used to work in previous versions with the CC module turned off.
But yeah, I take it like I’ve learned another new thing.
The developers are in a difficult position. Each additional setting makes the software harder to learn, so people complain. Each config option taken away reduces flexibility, so people complain.
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After some more edits, I have adjusted the display-derived D65 values a bit, as they seemed to give a new magenta tint that wasn’t right, either. But somewhere between the green-tinted default D65 values and the display-derived magenta-tinted ones, I found a good set of values that seems to work well for me.
I wonder, though, if these adjustments are actually reasonable, or merely a way of sneaking a tint slider into CC after all.
AP recommended a fix right…so display and all white screen…take a photo of your screen and then do a spot wb on that …not the correction… now use those as your D65 values… This should help correct for ambient impact and correct your D65 values if the provided ones are not correct…this I think is actually now mentioned in the manual…
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I tried it a long time ago even though I didn’t really have a noticable issue and because this can also help adjust for your ambient light…even when your monitor is not calibrated for white you will get a pretty good value… I would try it and see how it corrects for you…You will likely see a change in the red value and this is usually what helps…
That’s what I did, and it is what my comment was about.
Good to know that it worked also for you.
It’s always a tradeoff also if we’ll have perfect algorithms and perfect sensor profiles. The profiles may change also between lenses on the same sensor. For example I own a Viltrox AF 56 1.4 for Fuji X. Compared to Fuji lenses it’s a bit colder (more blueish). So also the lens affects the profile (matrix in darktable case). With modern white balance I had to use different white balance coefficients to fix this (the shot at a d65 calibrated screen provided different values between this lens and other lenses). With classic white balance you should manually tune the tint or coeffs but this will be different for different illuminant temperatures.
In general I agree but for me this removal of options can also lead to what for me is a dumb solution in that you currently have the CC module enabled with the CAT every time even when you have selected none or display as the new workflow presets. Removing the WB selection controls means that you get a conflict It means that if you enable it to do channel mixing or use one of the other tabs then you have to go and manually set bypass for your WB to be correct which is likely why you are using that workflow in the first place ie you want to use legacy wb.
I don’t follow why this was done or if it is an over sight but for those selecting and wanting legacy now there is an extra click and also the double wb warning… I know this can be disabled and you could create a preset to have CC in bypass but this seems like an unnecessary exercise esp for a new user…
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Understood…I was merely reinforcing that you are not likely sneaking anything in but merely correcting an improper reference value…
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I had a Viltrox 23 at one point, which tended a bit magenta. And an adapted Canon that was a bit warm. My first party Fuji lenses however seem very consistent (although this might be caused by some digital correction that isn’t available to third parties? Or is it due to consistent lens coatings? I have no idea.).
I think… The default for new users should be the scene referred using WB module at reference and the cc module. Advance users can set it to none and then use the new auto preset feature to apply whatever module setting they want… Does creating the auto preset not work for you?
Does that not seem silly to you?? Why have workflow setting of none at all then?? I can make things work but that should not be the way a software is designed IMO… just will create more reasons to call DT quirky and unorthodox… If the workflow starts with WB in a non reference state, ie as shot then activating CC module should be in bypass IMO and not introduce a change that wrecks that…
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I was also surprised by the removal: in my eyes, the two aspects (scene vs display referred workflow and legacy vs modern chromatic adaptation) are orthogonal.
Maybe those who have successfully fixed the D65 coefficients (e.g., by measuring a calibrated scene) could submit them to the developers as feature requests.
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I have a slight concern that the D65 coefficients acquired by taking a picture of a screen with a white LED backlight is not a very good approximation of actual D65 illuminant. Its spectrum is far away from actual daylight.
That said, it might be still good enough for some purposes. I also think an equally fair (if not better) approximation would be shooting a sheet of white paper in midday light outside (as that is what the D65 illuminant is modeled after). Would be actually interesting to try this.
To me, it’s mostly a matter of getting a fair starting point for demosaicing, but it’s not worth it to give it too much of a meaning. The bulk of the chromatic adaptation is done in color calibration anyway. And, lacking spectral profiles for cameras, we’re out of luck trying to create a universal color profile or a WB preset that works well in all conditions…
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It does not. There are other workflows like monochrome or non-raw. Having a None makes sense to me, so the user can create whatever workflow they want.
I’ve read somewhere that Styrofoam is a better white material than paper, as it won’t contain any fluorescent whiteners. And I have a color checker that should work well as well. I should also have a spare filament lightbulb somewhere that might also do the trick. I’ll experiment a bit, just for fun!
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