How does one emulate the LR's clarity slider in RT?

(Eric Mesa) #1

I did a bunch of Googling today and I can’t find an answer. Sometimes, back when I used to use Lightroom, I would use the Clarity slider as a subtle sharpener or desharpener. I didn’t know it at the time, but learned today that it’s basically changing the contrast of the midtones to give an appearance of more or less sharpness. Because of the subtlety of the effect, it was often nicer for producing a soft focus in post than messing with the global sharpness slider. (And going the other way, could create a grittier look)

What would be the best way to emulate this in RT? After browsing through the Wiki, I came up with a couple of ideas:

  1. Somehow use the sliders on the exposure tab to mess with contrast on the midtones. I’m not 100% sure how I’d do this, but I guess if I had a traditional S curve, there would be yet another S curve in the middle of it

  2. Maybe the sharpness by contrast tool? (Side note: Pat, I’d be curious what you think about this tool, because it appears to perhaps simplify the GIMP decomposition thing you do to fix skin. Or maybe, at least, it might give you a better starting point for that)

What do you guys think?

(Sebastien Guyader) #2

@djotaku regarding the clarity slider, I have no idea. But regarding Contrast by Detail Level tool in RT, indeed it is very useful for fixing skin blemishes / sking smoothing, but it will not be possible to have as much control as if done through wavelet decompose in Gimp, because you can not brush the mask to apply the effect exactly where you need. Of course you can use the slider to apply CBDL only to skin hues, but it may often interfere with non-skin areas having similar hue as skin.

(Eric Mesa) #3

Good point. Good point.


Hi Eric,

Yes, the clarity sliders in LR and ACR are believed to work by
raising the contrast in the midtones.

To achieve a similar effect in RT, I have been quite sucessful
using Curves, Contrast by Detail Levels, and Wavelets.


(Sebastien Guyader) #5

Maybe the Retinex tool can be useful too for “clarity”.

(Pat David) #6

Not sure if you’ve seen this but I looked at this a bit a while ago in GIMP/G’MIC:

Not necessarily as a workflow but it might be useful just as a reference to see what might be going on under the hood? With later versions of GIMP/G’MIC and high-bit depth it might be a more feasible solution of sorts.

Yep! I’ve played with a little bit. The problem is that I’ll often get down to small details and start fiddling with D&B or extremely targeted adjustments of wavelets to get things the way I like. If I’m going to do that anyway I’ve just sort of gotten used to dealing with those things at that point in my workflow rather than in RT.

For instance, looking at the PlayRaw with Mairi Troisieme in it

the results from everyone mostly didn’t do anything with the skin tones to the same level that I did in my version. I’m not quite sure that you can even target those modifications well enough to warrant any serious skin work in a raw processor (imo).

(Eric Mesa) #7

Can you give a rough workflow?

(Eric Mesa) #8

Makes perfect sense. I guess it’d probably be a good starting point and then go to your wavelet decomp afterwards.

(Jonas Wagner) #9

I haven’t played with Lightroom in a while but from what I recall it’s just local contrast enhancement using some something like an unsharp mask. I’d use wavelets & the tone mapping in RT for a similar effect.

(Eric Mesa) #10

Looks like there are many ways to skin this cat

(Carmelo Dr Raw) #11

Personally I use most of the time a technique inspired from Patrick David blog, where I replace the unsharp mask by G’MIC’s bilateral smooth filter, and restrict the effect to the midtones as suggested in the blog article.

The bilateral filter has the advantage of nicely enhancing the regions of small and medium contrast, while avoiding visible halos around the strong edges.

I’ll try to post an example some time tomorrow.

(Jud Johnson) #12

In Photivo, there is a slider under the lab contrast tab called texture contrast. That has been the closest filter/adjustment I have found to mimic clarity. The Lightroom clarity slider is suppose to work on midtone local contrast. You can adjust that in Photivo as well, but it won’t give you the same affect.


No, I do not have a specifc, universally working work flow to recommend. I am still trying to grasp what is possible/not possible with Wavelets :blush:

(Eric Mesa) #14

OK, no problem. If you ever come up with something, feel free to let us know.


I believe that “clarity” works by increasing the local contrast (while keeping global contrast constant). So in Raw Therapee the corresponding slider would be “Local Contrast”, found in the Shadows/Highlights Tool in the Exposure panel. Of course you can achieve a similar effect with other tools (CBDL, Wavelets), but Local Contrast would be the most direct and straightforward way IMO.

(Eric Mesa) #16

Hmm…I’ll have to explore that

(Desmis) #17

I do not have Lightroom, so difficult for me to make a comparison. But there RT in two ways to do something that should look like clarity.

  1. with Retinex : choose “Process: Unsharp mask”, in this case I use only the possibility of large radii (the rest of Retinex is not used). then you can change Method (low, …high…) and strength, and radius

  2. in branch “newwavelet”, in “Edge sharpness and Clarity”, select “sharp method = Clarity” (you can change in Wavelet settings : above or equal the level (default Level 7)., then merge luma and merge chroma…


(Stampede) #18

I was talking to another more experienced photographer over the weekend and showed him a picture that I shot inside an filthy abandoned warehouse. He was raving about how he would use the clarity slider in LR to really emphasize the grimy, dirty feel of the shooting location.

Reading about how Clarity works in LR, I wonder if I could do a layer with a luminosity mask in GIMP to confine changes to the mid-tones, and then adjust curves on that masked layer to increase the contrast. In theory, this should mimic the Clarity tool, as far as I can tell. Thoughts?

(Pat David) #19

Possibly? I had made a couple of notes a little while ago about this:

(Mica) #20

If you’re open to other tools, darktable’s equalizer module has a preset called Clarity. In RawTherapee, wavelet contrast or the contrast by details tools will do similar.

Lastly, share those filthy abandon wearhouses with us!