After-Before Friday Forum – Week 65 (Clarity in GIMP*)…

I would guess that if you were to ask a basset hound,  “What is the best thing about having long ears?”  They would have to say something along the lines of, “They make a great sleep mask.”

My basset hound can be found snoozing with her ear over her eyes 9 times out of 10.  My previous bassets did it too. 😀

I can’t resist photographing her when she is being super cute while taking a nap.  So when I needed a photo to try out a tutorial I found on Clarity in GIMP, this seemed like a good photo to try it out on.

Below is my experimentation of several ideas presented in that tutorial.  I have written up my own ‘tutorial’ below of the steps I took while following Pat David’s tutorial (see link above)…


Go find out what everyone else did this week for AB Friday Forum here.

I have joined ABFriday (after before Friday), it is a forum hosted by Ben at Aperture64. This week’s forum can be seen here.

Every Friday Ben showcases after/before photos we’ve submitted. Then, if we choose, we can tell how we did it on our own blogs.


Check out Pat David’s tutorial on Clarity in GIMP*, it is very well written and explains a lot.  I basically followed along with his tutorial, so this ‘tutorial’ is more of a show and tell.

  1. First, I downloaded the script-fu for Luminosity Masks from the GIMP registry.  A script-fu is basically a set of commands that are executed when you run the script-fu, much like an action in Photoshop.  Someone else has gone through the trouble of making the action and you can read the script to verify that it isn’t doing something nefarious (because it’s Open Source).  Pat David created a script and then Saul Goode improved upon it, Pat himself suggests using Saul’s script.  So that’s the one I downloaded.  You can then ‘install’ it into your GIMP by following these guidelines.Once the script is where it needs to be, you can access it in GIMP by going to Filters->Generic->Luminosity Masks (saulgoode).  You will get 9 channels, 3 of each Light (L), Mid-tones (M), and Dark (D)…channels
  2. Then I started to play.  I created an unsharp mask layer [Filters->Enhance->Unsharp Mask] using the obnoxious settings of Radius: 80 and Amount: 1.5.playing_with_clarity-gimp--unsharp_mask_LR1000-wmThen I applied the layer mask [Layer->Mask->Add Layer Mask] selecting the M Luminosity Mask Channel, which is basically creating a mask of the mid-tones.maskThere is a bit of color casting (purple in this case) around the edges of the ear..  this can most likely be adjusted with some tweaking, either by changing the intensity of the filter in the first place or even changing the opacity of the layer with the mask…playing_with_clarity-gimp--unsharp_mask-MLuminosityMaskApplied_LR1000-wm
  3. Next, I tried a Freaky Details layer (from the G’MIC Plug-in**) [Filters->G’MIC->Details->Freaky Details] at these settings: Amplitude of 4, Scale 22, and Iterations 1.  I also set my G’MIC filter input/output to these settings… gmic-input_output playing_with_clarity-gimp--freaky_details_LR1000-wmAgain, I added a layer mask [Layer->Mask->Add Layer Mask] selecting the M Luminosity Mask Channel.  This time the area around the edge of the alligator toy (the edge of the white mouth) has a bit of haloing but it doesn’t show up once the mask has been applied… playing_with_clarity-gimp--unsharp_mask-MLuminosityMaskApplied_LR1000-wm
  4. Lastly, I tried something I didn’t even know about, a filter called Local Normalization [Filters->G’MIC->Details->Local Normalization] at the default settings… playing_with_clarity-gimp--local_normalization_LR1000-wmAgain I added a layer mask [Layer->Mask->Add Layer Mask] selecting the M Luminosity Mask Channel. playing_with_clarity-gimp--local_normalization-MLuminosityMaskApplied_LR1000-wm

If I had to choose right out of the box no extra tweaking required, I think I’d choose the Local Normalization filter and mask.  This was a really neat experiment and a great and easy method of upping the clarity (aka mid-tones) of my images in GIMP.

After I wrote this, I was walking my dog with my husband telling him about this new-to-me concept and how much control I could have over the masks.  Suddenly, I wanted to try the Local Normalization filter with the 9 possible Luminosity masks (click to enlarge)…

As I was clicking around between the different layers, I started to see that I could combine a few of the layers to get a really specific look.  It’s been a few years since I’ve taken Discrete Mathematics, so I’m not sure how to do the permutation calculation but it would be a lot1 of variations.  Also consider that you could then change the opacity of the layers that you’ve chosen.  Oh the power! 😀   I’ve chosen LL, M, DDD (at full opacity) and I got this result…

For comparison, here’s a little slideshow:

This slideshow requires JavaScript.

Kind thoughts and comments welcome! 😀

This is definitely something I plan to use and play around with in the future.  It was a really cool find, and I hope that you check out Pat David’s tutorial for more information.

Until next time…

1 If you are curious about the math, I got out my Discrete Math book and also used this calculator. I worked it out to be 986,409 possible combinations of the nine channels (using full opacity), so you are really only limited by your imagination. 😀

P(9,1) = 9!/(9-1)! =       9
P(9,2) = 9!/(9-2)! =      72
P(9,3) = 9!/(9-3)! =     504
P(9,4) = 9!/(9-4)! =   3,024
P(9,5) = 9!/(9-5)! =  15,120
P(9,6) = 9!/(9-6)! =  60,480
P(9,7) = 9!/(9-7)! = 181,440
P(9,8) = 9!/(9-8)! = 362,880
P(9,9) = 9!/(9-9)! = 362,880

* GIMP is Open Source software that is available for all platforms (Linux, Mac, and Windows), it is a photo editor that does many (if not all) of the things you can do in Photoshop. You can download it for free here. The GIMP online manual can be found here.

**G’MIC Plug-in for GIMP is a plug-in that has a ton of filters, you can download it here.


Like Wilber? You can get him here.

5 thoughts on “After-Before Friday Forum – Week 65 (Clarity in GIMP*)…

  1. Oh my, that was lot of information. I am always impressed how well you are using GIMP, I think they should pay you for such a great job of advertising. 🙂 Your subject is super-cool, giving you an amazing starting point. I particularly like your last edit, combining all the different things seems to work really well.

Kind thoughts and comments are always welcome...

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