Lab Color model and painting - GFXartist.com - Served over 20,000,000 artworks

Back to forum overview

Back to topics

Lab Color model and painting
jfrancis \| 02/18/2004 @164 \| edit post

The Photoshop color picker can work not only in RGB and HSB, but in Lab color space as well.

L a b color space has 3 sliders -- luminosity, a red-green slider ( a ), and a blue-yellow slider ( b )

I've never found much use for the Lab mode, but I wonder if it might be better when painting to use the color picker in Lab mode. That way, if you want to darken and warm a color, you could lower the L slider, and move the a slider toward red. If you want to darken and cool a color, you darken L and move the b slider toward blue.

---
You can do the same in HSB by lowering B (brightness) and rolling H (hue) warmer or cooler, but the hue values change so fast it's hard to make small hue adjustments

Re: Lab Color model and painting
Foot \| 02/18/2004 @312 \| edit post

Lab does have a wider color gammut than the other color spaces (RGB, CMYK), so I guess that is why it exists... but I do find the whole color selection slider setup to be kind of wonky.

[Message edited on 02/18 @312]

Re: Lab Color model and painting
jfrancis \| 02/18/2004 @383 \| edit post

Why wonky? The L slider makes the color lighter or darker. The a slider makes it redde, the b slider makes it bluer. And the changes are slow and gradual. I think it's worth exploring.

Re: Lab Color model and painting
jfrancis \| 02/18/2004 @383 \| edit post

Why wonky? The L slider makes the color lighter or darker. The a slider makes it redder, the b slider makes it bluer. And the changes are slow and gradual. I think it's worth exploring.

Re: Lab Color model and painting
jawine \| 02/18/2004 @512 \| edit post

I sometimes use the lab color section of photoshop's big color circle, exactly for the reason you said, that it's easy to make a color a bit greener/redder or bluer/yellower than messing with cmyk values.
But just moving your hue to red or move away from red can give that effect as well, I just use what works at the moment i'm mixing something ^0^

The disadvantage is that lab has lots of colors outside cmyk gamut, and also outside rgb so if you like very bright colors and you pick them from lab mode you might use colors both screen and cmyk can't display. But well photoshop has this wee gamut warning triangle, unless you work in lab mode of course, so that might not be a big deal

Re: Lab Color model and painting
disenchanted \| 02/18/2004 @579 \| edit post

Lab space was designed to be perceptually linear. It's very handy in making computational models of color appearance or other aspects of the human visual system. I have never actually found a use for it in Photoshop tho...

Re: Lab Color model and painting
Foot \| 02/18/2004 @698 \| edit post

_quote:
jfrancis wrote on 02/18 @383
Why wonky? The L slider makes the color lighter or darker. The a slider makes it redde, the b slider makes it bluer. And the changes are slow and gradual. I think it's worth exploring.

I am not saying it is bad, I am just not used to using it yet for the reasons jawine said. I may explore it more though since you mentioned it.

[Message edited on 02/18 @745]

Re: Lab Color model and painting
jfrancis \| 02/18/2004 @782 \| edit post

_quote:
jawine wrote on 02/18 @512
I sometimes use the lab color section of photoshop's big color circle, exactly for the reason you said, that it's easy to make a color a bit greener/redder or bluer/yellower than messing with cmyk values.
But just moving your hue to red or move away from red can give that effect as well, I just use what works at the moment i'm mixing something

Circle? Are you thinking of Painter? I can't picture a circle in Photoshop. How do I get that?

...also yes, there are of course other ways, but the hue slider moves through so many hues so quickly that it's not as easy to make subtle changes, I think.

...and finally, maybe I'm slow, but I discovered while posting this topic about L a b that if you enclose a ( b ) in paerentheses, you get a little picture of a beer mug.

Re: Lab Color model and painting
Foot \| 02/18/2004 @786 \| edit post

The circle mentioned is for macintosh color pickers I think. I haven't seen it on windows yet.

Read the Terms of use and Privacy Statement.
This site is a property of Brothers in art For more information and support, contact .

Web GFXartist.com