Math explanations of Lightroom operations: Contrast, dehaze, Vibrant, and Saturation

[Einst_Stein]

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Can someone explain in Math what does it do in Lightroom when adjust:

1: Contrast

2: Dehaze

3: Vibrant

4: Saturation

[250swb]

Probably best to just see what happens when you adjust those sliders, although there are times when you can see but not understand why one adjustment seems to be doing something very similar compared to another. To cover this Adobe do offer explanations of how to use them and when, or Google's Ai response for say 'Lightroom Vibrant' is fairly good.

Edited February 14 by 250swb

[PhotoCruiser]

The sliders on this panel are the most i use,
mostly with moderation but heavy use can transform a 08/15 photo in a piece of art.
Whats the math behind them? I have no idea, but i know that they work great.
Chris

Edited February 14 by PhotoCruiser

[jankap]

I found much info in the book(s) and software of Dan Margulis. I still use the LAB colour mode, that he favours, in Photoshop. Furthermore, I have Lightroom too, but all my photos pass PS. But that is, because I started with PS 2 (or 3?) in 1998.

[evikne]

32 minutes ago, Al Brown said:

Try transcribing my binary text to english, the answers are there.

I asked ChatGPT:

Sure, here’s the translation from binary to English:

"Sure, dehaze ups the midtone contrast, contrast ups the overall contrast, vibrancy saturates not yet saturated colors and saturation all colors."

[LocalHero1953]

3 hours ago, evikne said:

"Sure, dehaze ups the midtone contrast, contrast ups the overall contrast, vibrancy saturates not yet saturated colors and saturation all colors."

Interesting. When it was first introduced Dehaze appeared to work as a combination of Clarity and reduced White Balance temperature. I have avoided it ever since for that reason: I prefer to use Clarity and White Balance separately. Clarity and Dehaze now appear to be two sides of the same coin: Clarity increasing contrast in the brighter midtones, and Dehaze doing the same in the darker midtones. But I shall have to play with it more to see exactly what is going on.

Edit. After watching the histogram while moving the sIiders, I see that it is only Clarity that actually increases midtone contrast. Dehaze shifts the central part of the histogram towards the dark end, but does not appear to alter contrast (except as collateral where the histogram bunches up to the left and stretches to the right). 

Edited February 14 by LocalHero1953

[Jeff S]

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Julieanne Kost provides good explanation, with examples.

For instance… Texture vs Clarity vs Dehaze…

And White Balance vs Vibrance vs Saturation …

Note that the vibrance slider, in addition to  comments above, is more sensitive to reds, oranges and yellows.

 

[PhotoCruiser]

vor 4 Stunden schrieb jankap:

I found much info in the book(s) and software of Dan Margulis. I still use the LAB colour mode, that he favours, in Photoshop. Furthermore, I have Lightroom too, but all my photos pass PS. But that is, because I started with PS 2 (or 3?) in 1998.

Same here; I started to use PhotoShop probably from V1 under Windows when i made a lot of computer graphics and websites (using the unlucky PageMill) and bought LightRoom when it came out from V1 on.
90% i use Lightroom Classic as it has all i usually need, for more "complicated" stuff i use PS.
In 2020 i used for 2 years Capture 1 as Lightroom had the pointer on wrong place problem, nice piece of software too, but finally i switched back to the Adobe products i know now for about 30 years.
Chris

Edited February 14 by PhotoCruiser

[Jeff S]

It should be noted that all the tools/sliders I linked above can be applied locally to just parts of an image, via masking, not just globally to all. 
 

The math can be refined.  Smart stuff.

[hansvons]

On 2/14/2025 at 8:10 AM, Einst_Stein said:

Can someone explain in Math what does it do in Lightroom when adjust:

Steve Wright wrote two books on compositing and colour correction for the VFX folks and are considered to be classics in this field. Because the maths and concepts are the same, reading his books for the interested photo editor makes a lot of sense. This is one is geared towards the beginner: 

Compositing Visual Effects: Essentials for the Aspiring Artist

And that one is his original work, the compositor’s bible: 

Digital Compositing for Film and Video

[M11 for me]

Am 14.2.2025 um 08:16 schrieb Al Brown:

Sure:

01010011 01110101 01110010 01100101 00101100 00100000 01100100 01100101 01101000 01100001 01111010 01100101 00100000 01110101 01110000 01110011 00100000 01110100 01101000 01100101 00100000 01101101 01101001 01100100 01110100 01101111 01101110 01100101 00100000 01100011 01101111 01101110 01110100 01110010 01100001 01110011 01110100 00101100 00100000 01100011 01101111 01101110 01110100 01110010 01100001 01110011 01110100 00100000 01110101 01110000 01110011 00100000 01110100 01101000 01100101 00100000 01101111 01110110 01100101 01110010 01100001 01101100 01101100 00100000 01100011 01101111 01101110 01110100 01110010 01100001 01110011 01110100 00101100 00100000 01110110 01101001 01100010 01110010 01100001 01101110 01100011 01111001 00100000 01110011 01100001 01110100 01110101 01110010 01100001 01110100 01100101 01110011 00100000 01101110 01101111 01110100 00100000 01111001 01100101 01110100 00100000 01110011 01100001 01110100 01110101 01110010 01100001 01110100 01100101 01100100 00100000 01100011 01101111 01101100 01101111 01110010 01110011 00100000 01100001 01101110 01100100 00100000 01110011 01100001 01110100 01110101 01110010 01100001 01110100 01101001 01101111 01101110 00100000 01100001 01101100 01101100 00100000 01100011 01101111 01101100 01101111 01110010 01110011 00101110.

Your link does not work 😮‍💨

[M11 for me]

vor einer Stunde schrieb Al Brown:

It is not a link

Of course, I know. Was not serious. I just liked your idea.

[jankap]

It is text. So DeepL should be able to handle it. Somebody give it a try?

Edited February 15 by jankap