U… er… what? can you do a screencast of how one were to do that? I can’t seem to follow… And I’d love to know how to use contrast equalizer…
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I’m definitely not going to make screencasts, maybe this will work:
We need a starting point so lets take this Play Raw entry image as a starting point.
Discard the history and open it in darkroom view, you should see something like this:
Expand, turn on the contrast equalizer module and make sure the luma tab is highlighted. This little sharpening how-to isn’t bothering with the other 2 tabs at all.
Select the difference blend by clicking on the circle in the mask toolbar at the bottom and select difference from the blend mode pull down menu. You end up with this:
The effect is easiest demonstrated when you use it over the full width (from coarse on the left to fine on the right). So put your mouse inside the square below the luma tab and use the scroll-wheel (towards you) to make it as big as possible.
Now go to the centre of the square and very slowly raise the bar. Look at the black screen and stop when you see the first sign of the cats right ear (viewer left). You see something like this:
Now turn off the blend by clicking on the circle.
Even though I used a real crude approach by using the ears and using the full width you can already see that this is much better then the first image:
Probably not that obvious this being a
The hardest part is deciding what needs to be sharpened and how much, but I really like the above approach a lot better then ogling it.
In this example I would probably focus on the finer parts (the hairs below the eye and next to the nose) by using the fine and some of the middle part of the spectrum. Something like this:
If the overall effect turns out to be to strong (or not strong enough):Adjust with the mix (effect) slider.
Hope this clears things up a bit.
EDIT: Replaced the 1240x600 “stamps” with 1920x1080 versions.
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Did you do this with the hue color picker? I thought I read somewhere that when you make a selection with the hue picker, the complementary color is selected by the hue slider. However, by your wording, “looked up the complimentary,” it sounds like you used an external color wheel instead. If you did, may I ask how?
By “toned down the luminosity” do you mean adjusted the factor slider in the negative direction?
Nope, I did not. Your interpretation of my wording is correct and the CB picker does give you the complimentary colour. Why did I not use it in this case? You can only pick an area and not a single point.
I used the color picker module and RGBto website. As of late I started using RapidTables - Web Colors.
A good colour analyser/converter is a module I miss in darktable…
If by negative direction you mean attenuate/make less then: Correct.
Thanks for replying. I checked out the color sites you posted by using the CB color picker, selecting 175, 143, 79. RGB to identified it as #af8f4f, hue 40, and provided a complementary color of #4f6fb0, 79, 111, 176, hue 220. On RapidTables, I chose the Color Wheel Tool, https://www.rapidtables.com/web/color/color-wheel.html, and entered rgb(175, 143, 79). It identified it as AF8F4F, hue 40. So far, so good. The complementary color was #4F4FB0, rgb(79, 79, 176), hue 240, seemingly off by 20. Duplicating that page and entering rgb(79, 111, 176) resulted in #4F6FB0 and hue 220, the hue I would expect. RGB to appears to be the better choice for finding the complementary. Another site, Color Wheel - Color Calculator | Sessions College, provides the same complementary, #4f6fb0, but it doesn’t indicate the hue.
I was especially interested in your experiment since Aurélien Pierre recommends using CB instead of curves rgb. I tried to duplicate the result of using curves and couldn’t come close. Curves is so easy to manipulate. However, what you have done here provides a learning path, and I really appreciate it.
There will be, slight, differences across sites/applications. I advise you to read the color balance section of the darktable tutorial.
Here’s a quote that might be of interest to you:
During the HSL to RGB conversion, the HSL lightness is always assumed to be 50%, so the RGB parameters are always balanced to avoid lightness changes. However, during the RGB to HSL conversion, the HSL lightness is not corrected.
I’m assuming you have, but just to make sure: Also have a look at Boris Hajdukovic’s (he’s on pixl.us: @s7habo) color balance only Editing moment. My little experiment was basically inspired by that video and in time other stuff fell into place to make me actually try it myself.
I’m glad to find out that people find this helpful.
I have read it several times and the follow on:
As a consequence, editing in RGB, then in HSL, then again in RGB will not retain the original RGB parameters, but will normalize them so their HSL lightness is 50%. The difference is barely noticeable in most cases, especially using the modes that already correct the RGB parameters internally in XYZ luminance.
What it said to me was stick to one method or the other, and that RGBL mode was better. I switched to RGBL mode, but found it impossible to use because the slider varied from -0.5 to +0.5.
I worked through Boris’ video and saved Snips of each step, the image and the settings. Now I am going to study it again.
One thing is obvious, you are able to see changes in the image that escape me; although, I am 71 and my eyes are not as good as they used to be, and my monitor is 7 years old, although I profile it regularly. But, yeah, this has been tremendously informative. I’ve seen your work on other discussions, and greatly respect it. I always work through your xmps.
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