[EN] darktable 3.4 new module : color calibration, get your Christmas lights back in gamut !

[@ntq1ty]

Thanks Aurélien for another informative and practical introduction to new features in darktable. Even though I have a computer graphics related PhD I learn something new about colour science with each of your videos that I watch!

[@kovacsistvankofa]

Aurélien, one must admire your sarcastic sense of humour :-D @20:24 'In case you're lost or you have forgotten, you have extensive tooltips here, and you see that when you hover the fields, they give you a big load of information, which prevents you from reading the manual, which is not necessarily a good idea, but... well' - I actually laughed out at that one. Thanks (for the information content as well as the humour)!

[@osmumos]

Thank you Aurélien for this details explanation of Color Calibration! I am new to photography and darktable. I have no prior knowledge of Lightroom and most of these color related concepts can get confusing. You explained quite well and I was able to follow. Thank you for all you are doing in the Darktable community.

[@jean-marcdecrock3888]

Bonne et heureuse année Aurėlien (et å ton épouse). D'immenses mercis pour tes apports dans l'évolution de DT et les tutos réalisés. Meilleurs voeux pour 2021

Bonne année à toi, merci !

[@emrg777]

Thanks for a great demonstration. I have been playing a little bit with the module. I must say the brightness and colorfulness tabs are addictive and impactful. Now just trying to get a handle on controlling them better and comparing normalized to unrestricted...

[@Giles29]

Thank you so much for all your hard work. Darktable is brilliant.

[@europlatus]

Thanks for this video, looking forward to playing with the module in 3.4. By the way, as a general rule, it's pronounced XY "Zed" in UK, Canada, Australia, NZ, and XY "Zee" in the US.

[@LucViatour-photographe]

Un grand merci pour cette vidéo. Première approche de ce nouveau module, encore difficile à l'intégrer dans mon flu de travail, je dois encore trouver des réglages à intégrer à mes styles.

[@VasylTretiakov]

Thanks for another great module. Speaking of "AI" overuse, why not use the "ML" (machine learning) abbreviation instead?

Because everyone now has heard about AI, while ML is… whaaaat ? It's really just end-user communication, at that point.

[@stulora3172]

Great video as usual. Long, but so full of valuable information that it is actually remarkable that it is not even longer! One correction (I am not a native English speaker, so I might be wrong): When you say "salvage", you actually mean "recover". Also, could you do a video, where you explain the colour models that "make sense" or are used at each point in the pipeline. Thank you!

[@philsmith774]

"This video has been recorded in HD 1080p at 10 images/second with mono sound...." - I'm impressed with the reason for this and how little impact, if any, it's had on my viewing experience. I can see a real difference as my CPU isn't working as hard, like it does when I'm playing other KZbin videos. Fantastic.

Yeah, if everyone keeps consuming and making videos as if it had no consequence, the whole thing will not be sustainable. For screencasts, which are mostly still images, 10 i/s is more than enough. I would go even lower if the video codec allowed it.

[@emrg777]

I think the adjustments that you can make with this module are awesome..one nice touch might be to have the option to toggle on and off the combined effect of changes in one of the tabs say brightness. So you keep tweaking the sliders for red green and blue but then you want to see what you have accomplished by this and unless you remember to grab a snapshot you have to zero them because toggling the module also affects the CAT or other tabs...so if there were check boxes to toggle the channels or at least the overall effect of the tab that might be useful....hopefully this makes sense....even a reset all to zero might be handy and then alternating this with ctrl z could provide that ability...just a thought ...again very nice..

I will think about that. Anyway, that's just v1, and you know me… nothing serious happens before v4 :D

[@FrankWalsh]

Very useful video. I miss black and white presets for colored filters (assuming panchromatic base film response). Is there a table of recommended settings somewhere for the common filters so we can easily create them as starting points? I also find myself continuously baffled by the normalize checkbox. It seems to make things less predictable in black and white.

The normalizing aims at keeping the sum of all coeffs = 1, which has no ground either on a physical level or on a perceptual level, but makes users happy, so don't ask me… As for emulating filters, just tweak the coeffs until you find a look you like. To do a proper emulation, I would need spectral transmittances of the filters, which requires putting a spectrometer behind a filter and blast a standard D50 light through it, then multiply the measured transmittances by the CIE 1931 XYZ 2° color matching functions. Anyone not having access to that kind of gear will only produce bullshit emulations, so the best guess is just to eyeball it.

[@kierowcabezpieczny]

I have a Panasonic D9 camera, and when I make a picture of a white picture and then open that in Darktable 3.4 the color looks just crazy! It is kind of green or something. Very frustrating. Pierre, could you please provide a step-by-step instruction on how to calibrate my white balance in DT? Like: 1. Make sure your monitor is calibrated to D65 2. Set your camera's white balance to ... (5500K? 6500k?) 3. Open a perfectly white picture (for example made in Gimp) and take a picture of it 4. Open the RAW picture in DT and.... etc I would really, really appreciate that. Thanks in advance and for your great work!

Hi, please see the doc : darktable-org.github.io/dtdocs/module-reference/processing-modules/color-calibration/

[@sunesnigel]

Amazing work Aurelien. I will start supporting your work tonight or next week. How can I add Fill light again? I can't seem to find it after the update. I see it has been replaced by the tone equlazier. The TE is very powerfull but it's time consuming to setup and I'm always having a hard time with it. I usually start with exposure, filmic and then fill light. I have abandoned the TE cause I always end up tearing the picture appart.

[@sunesnigel]

Never mind, Ive played around with it now and I think you've improved so it's more really easy to use! Again, amazing work.

[@Foche_T._Schitt]

Thoughts on ColorCalibrater module by VFX Grace?

Too expensive ?

[@Foche_T._Schitt]

@ Not to be confused with Darktables new Color Calibration module. It seemed like the quickest way to color correct with a color checker.

[@mstraeten]

@@Foche_T._Schitt darktable current master is quite quicker on this task ;)

[@Foche_T._Schitt]

@@mstraeten What? I see no feature which color corrects using a *color checker* other than Darktable-Chart which is a slow process that has never worked for me. It wont launch. If I change lighting, I need my color checker. If I changes lenses, I need my color checker. If I switch bodies... It makes no sense to calibrate the camera body using darktable chart when everything else is constantly changing.

[@mstraeten]

@@Foche_T._Schitt it’s in the codebase for next release: github.com/darktable-org/darktable/pull/7293

[@gpagnoni]

Hi Aurelien, it seems that the links to your website don't work - at least here, with Safari or Chrome, on Mac OS X Big Sur. The error message: "Il semble que votre installation PHP ne possède pas l’extension MySQL nécessaire pour WordPress."

Great, that website broke again… Thanks for letting me know, I'm not sure what the cause was, but it seems I have fixed it now.

[@clairedebalzay7848]

thank's, and in french ;-)

Je n'ai pas le temps de tout faire en français… Je compte sur les youtubers francophones pour prendre le relai à partir d'ici.

[@briansrcadventures1316]

(Not sure what happened to my reply!) A great video, Aurélien! I'm looking forward to Darktable 3.4 That's also quite a nice theme on Fedora (KDE?) It certainly seems more useful to have the panel on the left, rather than on the bottom especially on a 16:9 ratio monitor :-)

It's Fedora KDE indeed, with just the shipped dark theme (whatever its name). The right bar is just me mourning Canonical Unity panel. I still don't get why all GUI, including websites layouts, are still thought to be vertical first while it's the smallest dimension of the display.

[@briansrcadventures1316]

@ Yes, it certainly seems a better use of a 16:9 widescreen monitor to have a panel on the left :-)