I’m starting a new series of darktable tutorial posts divided into two categories:
- Fundamentals: instructions about fundamental parts of the scene-referred workflow, from how to capture an optimal exposure to developing the RAW file to a finished state
- Creative Effects: instructions for how to apply a variety of artistic effects to your photo once you have developed it
While my depth of knowledge is more limited, I hope this can be a complement to the excellent video tutorials by @s7habo, @Bruce_Williams, and others.
Tutorials so far:
I’ll do my best to answer questions and am open to suggestions for future tutorials!
well done with the tutorials. They are clear and easy to follow and I believe for many people they will be a better format than a video. You have effectively used screen shots and guided the learner well. This sort of tutorial would work best when the learner can have one screen showing your tutorial and on another screen they have darktable open doing the edits themselves. Great work.
I added a new tutorial today:
In your Reducing Chroma Noise in Water, you say that the contrast is a display-referred module. In darktable, the tooltip indicates the input and output of contrast equalizer is “linear, LAB, scene-referred”
Thanks for sharing your content…to be fair you should have used the chroma only preset in denoise or actually added that in addition at the end to show that you can use it just for that… Just a thought
Wow, I am surprised! I didn’t think any of the LAB modules could be scene-referred
I thought the guidance in recent releases was that both types of noise can (and should) be handled with a single instance of the module now? Or you’re thinking that the chroma only preset would avoid the detail loss associated with the default denoising?
I think that was your title, ie chroma noise. Indeed for many images chroma noise is all that is needed to be handled. And in your sequence you presented a couple of chroma only solutions and then used denoise with luma and chroma active so not a fair comparison of using this module for chroma noise. This is infact why it comes now with one preset ie one for chroma noise. Depending on the noise I try to get away with only CA module if possible. It really can be effective but then if not I use the denoise profiled chroma preset. If there is luma noise and you use this module for sure you need to tweak the settings and dial it back not to lose details. I have also gone to using the color preset and astro denoise with the patch at 4 and the strength at around 12% This is really nice in many cases for fine grain and luma noise if you want to remove it. The other one I will use is surface blur. Using this with a small radius is also awesome for luma noise and you don’t lose much detail… There are lots of ways to do things for sure… I was just trying to point out that for that module and how you laid things out you should have done a chroma application to compare
Thanks for the detailed explanation; I agree that it’s not really a fair comparison of what denoise (profiled) can do for chroma only, so I’ll update that section to use the preset.
On the luma side, I am excited to try out those astro denoise and surface blue settings on an image which needs more denoising! I’ve been pretty happy in general with the detail preservation in denoise (profiled) (especially with preserve shadows dialed back) so if these other modules can do an even better job in some cases, that would be great!
I think it can be situational and I suspect that you could tweak luma noise with the contrast eq, diffuse and sharpen, surface blur ie the old bilateral , or astro ie the old non local means both updated I think… Or tweak the wavelets in profiled denoise. The reason I sometimes go the other route is with fixed settings I can apply that if needed so no tweaking sliders. I think I used to drop the preserve shadows and drop the strength to ~0.3 or so for profiled denoise. Then you are using a common strength setting you have to tweak the curves in the module for differential treatment so in the end I bounce around a bit and try different approached depending on the image…
Todd, are you referring to the astro denoise module or another module? I can’t seem to find that preset.
Chroma preset of denoise profiled
Hi Thanks for your tutorials, I really like the richness of content the choice of a website/blog gives you. You exploit this quite well. the combination of text/before-after slider image and video is, i think, a plus over a stand alone video
I’d be delighted to see your tutorial base grow, it can be so useful to very new users and maybe tackle some stuff more advanced users are looking for like tricks shown by @s7habo .
The only thing that bothered me a bit was the video quality, I guess it’s online storage or bandwidth constrain that made you select this level of compression, do lowering the frame rate or changing codec could fix that though I don’t if it’s already the winning combination
Glad to hear you’ve found it useful! I am definitely open to ideas for future tutorials too.
The video quality seems good to me (e.g. I don’t see any pixelation at 2560x1440 in fullscreen) - what quality issues specifically are you seeing? The framerate is low since we’re mostly just interested in a series of screenshots of each of the modules with their settings (verses smooth transitions/animations when navigating between modules and other effects)
On this video ( Color Contrast | Avid Andrew ) especially I see this grainy look but not on the other ones so not a big deal I guess
These tutorials have been great! Darktable is re-inspiring me to shoot again after a long break.
I did have a challenge: how to revert Darktable appearance back so that I can all those controls in darkroom below the photo?–the lightbulb, the over/under exposure meters, etc.
I can’t see them after I tried messing with the font size. Tried messing back with size, with the system default size, with the GUI, nothing made it re-appear.
I see those little white arrows that help minimize the tabs on the left/right and film strip at the light table, but not when I switch to darkroom.
Any advice would be appreciated.
h key to display hotkeys for the given view you’re in
I found it! It was Ctrl+b/b
Happy New Year! Let’s celebrate 2023 with a new tutorial that features the sigmoid module introduced in darktable 4.2: