Depends on what kind of blur you want to correct. That’s why there are multiple presets, and all those sliders 
In the case of Rawthetapee or Lightroom there are no such options and I have a hard time understanding the D&S module. In RT or LR you turn on the tool and slightly adjust the strength. The effects are very good. Here in DT it’s all complicated
It is a powerful, yet complex module. And the sliders don’t have good labels. But it is worth investing in learning the details. I would recommend
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Depends on the source of the blur and how much sharpening you want. The “Demosaicing” preset should correct the small blurring due to the demosaicing (interpolation over a few pixels). “Lens blur” may be aimed at blur due to diffraction in the lens, “Sharpening” does what it says…
THe best way to learn what the module does is to try the presets… (if you don’t like the result, just switch of the module). Keep in mind that you can use several copies, I often use “demosaic”, and one or more of “lens deblur”, “local contrast”, and “sharpen”. And I always use “profiled denoise” with DorS…
Keep in mind that perceived sharpness depends mostly on edge contrast, if there is enough fine detail: an image with a lot of fine detail, but low edge contrast will appear less sharp than an image with high edge contrast and possibly less fine detail.
With DorS, you can get :
- a (small) increase in fine detail : presets like “lens deblur” or “demosaicing”,
- or create more edge contrast: “local contrast”, “sharpen”
In all cases, the effects are less pronounced than what you can get with the “sharpen” module, and the presets aren’t likely to cause artifacts (if there’s not too much noise in the image, if there’s noise, and you start pushing the module, you can get unpleasant artifacts due to that noise).
On the other hand, modules like “sharpen” can cause halos when over used (so can any process based on Unsharp masking)
It is also a matter of taste, personally I’m not always a fan of “tack sharp” images…
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You can do this in dt too. There is an older module called “Sharpen.”
@Damian_J I use the preset sharpen demosaicing AA filter as my default initial sharpening for all my images as my cameras all have an AA filter. For many images this is all the sharpening I need.
If I have a soft shot due to lens quality or focus I may use lens deblur presets as a second instance. Also a really useful preset I got from another forum user is called texture. I have included a screen shot of the settings so you can replicate it. It works great for many images, but is not suited for all images.
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Since Terry shared this I would add that those last two sliders can really help to dial in the effect…ie to clean up artifacts or to enhance the impact of the settings in the rest of the module… those are two key sliders to play with when using this module…ie the edge sliders…
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DT has those simple tools as well. You can just use those. For something in-between, in terms of complexity, there’s contrast equalizer.
Diffuse or Sharpen is a powerful, generic tool for doing both diffusion (blur) and sharpening, which works on the principle that to sharpen you simply run diffusion in reverse (or vice versa, as you prefer). It lets you choose the range of detail to work on and how much to diffuse or sharpen different parts of that range. It even lets you sharpen one part of the range while diffusing another.
One big difference between the classic sharpen module and diffuse or sharpen, is that the unsharp mask used by sharpen doesn’t really sharpen, but rather increases local contrast, which is why it can lead to haloing if pushed too far. Diffuse or sharpen, on the other hand, does something that is very close to true sharpening, which you should be able to push much further without things falling apart.
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I don’t know what “true sharpening” would be (maybe regularized deconvolution using physical characteristics of a lens measured on an optical rig?), but D&S just uses a more sophisticated way of local contrast management which is much less artifact prone than naive sharpening.
D&S is kind of a sweet spot between power and complexity. I just wish those sliders were labelled better. Until I looked at the source code I used to believe that “3th” and “4rd” orders had something to do with an expansion, which was a huge misunderstanding.
improved the tooltips a lot.
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