Curves

unpopular · Jan 21, 2012

gerardo2068 said:
Can you give me example where I would want to you use Curves adjustment in a specific color channel? Like on the drop down menu you can choose red green or blue. I understand the RGB setting. You could use it to make it brighter or darker, add contrast and things like that. But beside a few tutorials where they use the other setting to make the photos looks pastel color, I can't think of any other situation. I'm beginner on PS.

There are SO many situations that you'd want to do that, it's hard to think of just one. Toning a black and white image, for example.

But also if the shadows have a blue cast, it's easy to correct by dropping the shadows in the blue channel, making them more yellow. Any time you have a color correction in a specific tonal region you'd use RGB curves.

unpopular · Jan 21, 2012

Ysarex said:
I achieve a similar result with saturation in Photoshop by accessing the Lab color channels independently

HLS and LAB are very similar in a lot of ways. I usually prefer HLS over LAB. I'm curious how you adjust relative saturation in LAB?

In either case, to access LAB adjustments in Photoline you don't have to convert the whole image first, you just switch to LAB in curves (etc). Which is nice.

gerardo2068 · Jan 21, 2012

I see. Most tutorials just explain the basics and most focus on the brightness and contracts. I would like to see more showing situations like color tonal correction. I will keep searching.

MTVision · Jan 21, 2012

gerardo2068 said:
Can you give me example where I would want to you use Curves adjustment in a specific color channel? Like on the drop down menu you can choose red green or blue. I understand the RGB setting. You could use it to make it brighter or darker, add contrast and things like that. But beside a few tutorials where they use the other setting to make the photos looks pastel color, I can't think of any other situation. I'm beginner on PS.

Some people use curves to fix skin tone by adjusting the individual colors as well.