I know a few people have asked about Lightroom equivalents, highlight/shadow sliders, how to replicate, etc. I have played with a copy of lightroom recently and made a few observations.
It seems like the exposure, highlight and shadow sliders are most closely related to the lightness slider in RawTherapee. Obviously, there is a luminosity mask to block off bright/dark parts of the image in Lightroom according to slider.
Is there a way to create a shadow lightness and highlight lightness slider in RawTherapee? Sorry if this has been asked before.
@Jud_Johnson mostly nobody here knows what “shadow lightness” or “highlight lightness” are, what exact effect they have. Screenshots before|after and a link to Adobe documentation would help.
Do you mean that you want a means for adjusting the highlights levels and shadow levels independently? Have you played with the Shadows/Hightlights adjustments in RT? That might get you closer to what you’d want?
There’s quite a few different ways to approach modifying certain tones in RT and a bit of experimentation can be quite rewarding. You can also fiddle with Retinex, Tone mapping, Tone Curves (in Exposure), and others.
@Jud_Johnson I’m not that familiar to RT yet, just started to use it some weeks ago, but as @patdavid said, I think it’s a combination of Exposure and Shadows/Highlights so here is a quick comparison.
LR: just the Basic Exposure, Contrast, Highlights etc. are used, all other is off
patdavid Yes, I’ve worked with the Shadow/Highlight on the exposure tab, but the tonal range sliders screw me up. I get black areas or washed out areas. It’s almost there, but not quite.
Morgan_Hardwood Yes, I know no one here knows what[quote=“Morgan_Hardwood, post:2, topic:1809”]
“shadow lightness” or “highlight lightness”
[/quote] are because it doesn’t exist yet. I was wondering if something like it could be created for RT. However, I might not have been as clear as I could have been.
So, is it possible to create a slider in RT that acts like the lightness slider in RT, but has a luminosity mask of some sort that causes it to only act on the shadow or highlight range of an image. Therefore, mimicking the Highlight and Shadow slider of Lightroom.
@Jud_Johnson no need telling me it doens’t exist yet Point is that most of us don’t have Lightroom, and as many of us don’t even use Windows, we can’t just install it to check, so if you ask for help regarding some Lightroom effect, be sure to supply before|after pictures which show what that effect does, or a link to documentation which demonstrates that clearly.
Thanks @martin_malepo, that demonstrates it well. Lightroom’s shadows/highlights sliders do some smart things under the hood, and I know of no libre photo program which has equivalents.
(clarification: I’m not saying that libre programs can’t recover shadows and highlights, but that the ones I know don’t have tools which work in a comparable way)
The way things go, usually one starts with a research paper, then someone implements the idea, and someone else helps with the UI. If you find a paper which explains how LR’s shadows/highlights tools work under the bonnet, then perhaps someone can try implementing them.
Well, now we can’t forget it because it might be something we all want!
The problem is that not many folks have ever used Lightroom to really understand or know how this is being implemented. If we can describe what might be happening in a more concrete way, it’ll give the developers something stronger to start with (these development weenies prefer to have something concrete - they can just sort of take off and start implementing if we’re clear enough).
So, maybe we can all try to define a little better what we’d like to see that does something similar? Can we produce some sort of test pattern to help @Morgan_Hardwood and crew to implement something quicker? Maybe a generic test pattern image to run through to compare the output with?
well it’s not the same but comes close - so @Jud_Johnson was right I think, the magic is probably some luminance masking, well may be.
I know @Morgan_Hardwood this is not exact sience and there would be for sure other ways to get it to this but I wanted to know how it would act with luminance masking
ah and next time I use RT for exporting the neutral TIF … now I wonder if that would make a difference …
@patdavid your idea about a test pattern is great I think - that zebra isn’t the best for that, thats sfor sure, so any idea what would be a good reference?
Ultimately, we can probably ask for something along these lines:
Can we generate a luminosity mask for use from within RT?
Can we have that mask applied in a new module that allows us to modify tones?
Can we have control over which tones of the mask get used?
I could see three sliders being used here, maybe four.
Highlights tone control to pull them brighter/darker
Shadows tone control to pull them brighter/darker
A slider to control the crossover point of the luminosity mask.
a. Optionally, two sliders - one for crossover point, the other for tonal “width” that the mask is applied to.
Hello !
Being quite familiar with Gimp (which is not the case with RT that I have been using for a few months only), I personally find GIMP’s “shadows-highlights” script-fu very convenient and easy to use (adapted from Dennis Bond’s original script, 2007).
Greetings,
gpzt ( Guy Poizat, Cabestany, France)
Point is that most of us don’t have Lightroom, and as many of us don’t even use Windows, we can’t just install it to check, so if you ask for help regarding some Lightroom effect, be sure to supply before|after pictures which show what that effect does, or a link to documentation which demonstrates that clearly.
and experimented a bit.
… now I wonder if that would make a difference …