I am wondering what sharpening strategies people use in DT and if my choices are flawed. I usually apply the demosaicing AA filter preset from the diffuse or sharpen module (D&S). If I want extra sharpening I then create a new instance of the D&S module and use one of the lens deblur presets. I often apply local contrast which adds to the impression of sharpening amongst other things. It would be interesting to see how others work.
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I am certainly no expert, but I use the Contrast Equalizer module to Deblur: Fine Blur: Strength 3. Sometimes I do multiple instances of this same action.
Thanks for your response Tim. I was just preparing some notes for a class on darktable sharpening and I stated that I thought the deblur options in the diffuse or sharpening (D&S) module were superior to the contrast equalizer modules (I am willing to stand corrected on this). Have you experimented with the options in the D&S module?
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I use the no AA preset. I have in the past used dehaze. I find for most cases the no aa used with 2 to 4 iterations is enough. CE can have halos if pushed and D and S can create extra grain and or noise/artifact if pushedā¦ The key for either is restraint
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For low ISO photos with fine details, that deserve peeping, I am gently using the sharpen module, radius about 1,5, amount like 0,8 or similar, details threshold over 30.
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I created a diffuse or sharpen preset which works great on pretty much all images:
deblur i20.dtpreset (1.2 KB)
It is a variation on the standard deblur presets, masked out of highlights as I usually donāt want to sharpen clouds or bright lights, and with a details mask so it only effects edges (itās intended for fine detail), which really helps prevent increasing noise on noisy images.
If Iām working fast I can usually just apply it and move on. For fine tuning all thatās needed is to adjust iterations (usually less iterations for portraits), and on odd occasion the details mask.
I find diffuse or sharpen gets nicer results than sharpen module, or contrast eq. If I didnāt have a good gpu Iād use contrast eq.
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No, I havenāt. And I am puzzled as to how or why they would be any different. I will try to research - thanks.
Because diffuse or sharpen is based on a physical model, rather than on an abstract signal processing model like wavelets. And even if it werenāt, sharpening methods differ from each-other, otherwise there would only be āunsharp maskā or āhigh-passā.
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I like the D&S module and I often tune the module per picture. The find the contrast equalizer also to be a good option for fine sharpening if you use the last to levels moderately and it is the faster option, as D&S isnāt the fastest one. In a lot of pictures it makes no differences, if you use the one or the other - itās nearly undetectable as far as I am concerned.
That said, Iām not a fan of sharpening at all. I think for an output resolution of 4K or below (with some output sharpening applied) you donāt need any sharpening at all. In a lot of pictures I would rather soften some parts - speaking of portraits for example. In portraits general, I would just mask the sharpening to the eyes of the personā¦
Can not comment on highpass or the sharpen module, as I donāt have enough experience with them.
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Interesting, I did not know that Darktable allows importing presets as well. Mainly I use my own presets and did not use the export option but experimenting with new presets would be fun!
How to import presets?
I know how to import styles, but if I select āall file typesā in there and choose my dtpresets, Darktable seems to import nothing.
ok - nice and good, Iāve read this passage as well but the the import procedure sounds very vague:
User-defined presets can be imported from exported
.dtpresetfiles using the āimportā button at the bottom of the screen.
this tells me nothing, where I should look for this button. A screenshot would help
- The hamburger menu of Presets allows to save new presets but not to import any new preset.
- the
Stylemodule in lighttable imports styles only - and if I try to import anything else than styles, Darktable does not import anything. - Finally, the
importmodule in lighttable hangs, cannot use it. Usually I import new film rolls with a script so I did not notice that theimportmodule is buggy on my machine.
The manual section you were referred to, is for the āpresetsā section of āpreferences and settingsā. That happens to be a (dialog) screen. At the bottom of that screen, there are a few buttons.
Thatās a completely different matter. But youāll have to be a lot more precise about the problem there to get help. And if at all possible, that should be in a new thread, or on github if itās really a bug: software rarely is buggy just on one machine)
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Since I dont use the import module, the import dialog took awhile to index/load the default directories. To test if this is a bug, I quit and restarted Dt. Upon next launch, the import dialog worked nicely, so both issues are resolved.
Sorry about being so terse, I was on the phone. Normally, I would have included a screenshot. Iāll try to at least add something like āsee the docs for Preferences ā Presetsā next time.
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No problem !
Fun thing, only afterwards I noticed āpreferences and settingsā in your link. Sometimes it is easy to miss the hints when they are in front of our nose
Great preset!
What I would like is a quick way to apply an instance of DorS with the i20 preset. One way to do this is to create a style that only has one module activated ie DorS with i20. Then its just 2 clicks to apply.
However, I have a baseline style which includes a DorS instance with the āsharpen demosaicing no-AA filterā applied.
Normally I apply my baseline style to a photo, then review what else is needed. If I now apply my āi20ā style it creates a second instance of DorS which goes below/before the baseline āno-AA filterā instance.
The manual suggests that the āno-AA filterā should come first.
Any thoughts on how to make this happen automatically?
Actually, from the manual, I understood that denoising should come first (applied first, so towards the bottom of the stack), then apply from coarse to fine, with āsensor and demosaic correctionā last (i.e. towards the top of the stack).
If you use that, it seems the order you get is the recommended orderā¦
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Glad you like it 
I donāt know why your 2nd instance of DoS is automatically being put before the no AA instance. Whenever I add a 2nd instance it automatically puts it above/after the 1st. Itās possible you have set a funny module order for DoS in that baseline style?
I have a style with multiple instances of DoS in the order I wish to use them. They are turned off to start (faster computations when working with other modules), but when they are eventually turned on, they are in correct order. I donāt use the no AA filter preset, but if I did, I would also put it before my i20 preset.
Iām not sure your level of knowledge. Module order can be changed by holding cntrl + shift, then dragging the module where you want it go.