View Full Version : Channels


Prisma
08-09-2007, 05:43 PM
I've been seeing people mention adjusting channels and fixing up portions of channels. I've played a little by look at the channels option in Photoshop and tried googling channels photoshop but I haven't found much to helpful.

Any suggestions, tips etc?

Thanks!

Swampy
08-09-2007, 05:53 PM
Prisma

There are some good books on channels. Deke McClellen's for one, Scott Kelby's for another. Also, you can take out a 1 month membership at Lynda.com and access Deke's Tutorial series on channels 24/7.

Graphics23
08-09-2007, 07:50 PM
I posted an introduction to understanding channels (http://retouchpro.com/tutorials/?m=show&id=291), and there's also a discussion thread (http://www.retouchpro.com/forums/rp-tutorials/17664-photoshop-channel-concepts-power-ten.html). Feel free to post questions there and I'll jump in.

Also search for articles on using the Apply Image, Calculations, and Channel Mixer commands.

It's also important to have an understanding of Blend Modes.

Meanwhile, here's a quick example of using channels to restore an image:

49114

In this picture not only is there a color cast, but there are yellow stains on the brides face.

The first thing I did was look at the individual channels and noticed that the stains were only visible in the Blue channel, but the Green channel looked pretty good. So I created a Channel Mixer Adjustment layer and used it to replace the Blue channel with the Green.

49116

Then I created a Curves Adjustment layer and did some basic color correction.

49115

The stains and color cast are gone and it took less than a minute. This is not necessarily the final image, but I'm in much better shape for further restoration.

Regards,

Michael

Swampy
08-10-2007, 07:12 AM
Excellent mini tutorial there, matey!

des151
08-10-2007, 07:33 AM
Michael,
Thanks for the tip. I haven't used Apply Image or Calculations, but I will learn how to use them.
Ray

Graphics23
08-10-2007, 08:06 AM
Excellent mini tutorial there, matey!

Arrrr...

I thank ye, Madame! Comin' from so accomplished an elucidator as ye'self, I be right honored!

Arrrr... :D

Michael,
Thanks for the tip. I haven't used Apply Image or Calculations, but I will learn how to use them.
Ray

You're welcome!

I have a bunch of Apply Image and Calculations examples floating about and I promised Lurch a tutorial on channel blending.

They all tie together, so I'll try to post something soon.

Regards,

Michael

dmrdm
08-10-2007, 10:03 AM
I purchased The Photshop Channels Book by Kelby a while back. It is worth it if you want to learn more.

Swampy
08-10-2007, 10:20 AM
I have the Kelby book too, but I find that many of his "techniques" are more on the "effects" side than real world workflow.

Michael.. Here's my color correction. I did a blur layer (masked) for skin tones on her face (didn't spend a lot of time here) and also an S Curve to pop it a little.

DJSoulglo
08-10-2007, 12:53 PM
Be sure to check out (if you can find it, it's a bit elusive)

Photoshop Channel Chops, by David Biedny, Bert Monroy and Nathan Moody.

Published by New Riders.

It's an explanation of most (if not all) things to do with channels.

Good luck!