[Doug Nelson]

Reading how many ways there are to view differing b/w channels I had a little idea. Perhaps someone with the requisite skills could turn it into a plugin or an action.

What I envision is having your image, clicking on the filter or action, and getting a one-page view of the individual RGB channels, the individual CMYK channels, the L channel from LAB space, and anything else that comes to mind.

A plugin filter would have the advantage of being able to view them on a single page, clicking on them, and having that view become your working layer.

An action might just have to do 3 duplications, 3 conversions, then 3 channel splits (although if you watch the automated contact sheet they have a way of putting them on the same page, which would work if adequately labeled, and might even work out better, since you could print it).

So, any takers? Is there someone that feels up to this?

[jeaniesa]

Doug - I have no idea how to do this, but it sounds REALLY cool!! I'd also like the ability to move the images on the contact sheet around so that I can view to similar ones side by side. (I.e., I often find it useful to compare the cyan channel from CMYK and the red channel from RGB side by side.)
Jeanie

[Ed_L]

That's a great idea. I wouldn't be the one who has the skills to do it though.

Ed

[DannyRaphael]

Funny you should mention this, Doug. I was messing with an ATN just the other day along these lines.

I started out with the vision of plunking down the individual channels side-by-side in the same document and somehow labeling them appropriately or doing as you suggested (individual files, properly labeled and doing the automated contact sheet thing). After struggling awhile came to the conclusion that the channel split method works for my purposes. One can easily hide / show / position chanel images for easy on-screen side-by-side comparision.

Far as I know 5.5 doesn't have menu commands (that work in actions) that will shift Photoshop into Full Screen mode, hide all the palettes nor "tile" images on-screen. Not a showstopper, but a little annoying.

The new PS7 scripting engine probably would enable one to get around any ATN limitations, but havn't got there yet. (I've learned so many programming languages over the years, the prospect of another one doesn't float my boat. Maybe in 2004!)

Doing the ATN in 5.5 would have the advantage of (theoretically) being compatibe with Photoshop 5, 5.5, 6, 7...

I'll fine tune the .ATN I started, put a few "STOP - comments
and post it -- probably late Thursday night -- for evaluation and field testing. If nothing else it will give folks something to chew on and improve.

~DannyR~

[jerry]

Doug

You read my mind. After Flora discovered the huge detail in the cyan channel of the current challenge, I thought it would be so helpful to be able to see all of the channels at the click of a button. I even started to read about actions.. Having no experience with actions, I am approx. 10 years away from being able to create this.. I hope Danny has success.. It would be a great first step in any restoration..

Jerry

[DannyRaphael]

OK gang... Here's my first public posting of an action.

Purpose:
This action will generate and display the corresponding RGB, CMYK and Lab channels for a given image.

FAQ:
* Will this action run under "my" version of Photoshop?
I believe so. This action was written using Photoshop 5.5, so it should work in Photoshop 5, 6 and 7 as well.

* Will this action work on a Mac?
As far as I know, yes... But don't hold me to that. (Would someone from the Mac side of the world care to comment?)

* How do I try this out?
- Right-click the attachment icon below and choose SAVE Target As... from the menu. This will initiate the download. Select a convenient place on your hard drive, e.g., your Desktop, to save the zip file. It's small, so it should only take a few seconds.
- Unzip the action. Save the "Split Channels.atn" somewhere easy to get to, for example, your Desktop.
- Open Photoshop.
- View/Show the Actions palette.
- Open the Actions palette menu (click/hold the triangle at the top-right of the palette) and choose LOAD ACTIONS
- Navigate to the location where the .ATN file was saved on your hard drive, click on the filename (so it highlights) and click LOAD. This will append the .ATN group to the BOTTOM of your Action palette.
- Scroll to the bottom of the Action palette.
- Click the 'triangle' to the left of the Action group name (Split Channels). This will display the actual action within the action group.
- At the bottom of the Action palette click the PLAY icon (triangle) and follow the screen prompts.

Limitations
1. It is not completely automatic end-to-end. There are a few things Photoshop actions cannot do.
2. It will work if there are multiple images open, but only if the target image is the LAST image listed in the WINDOW menu.
3. When the action is complete, a prompt will instruct to
* Hit the TAB key (to hide palettes)
* Select TILE from the WINDOWS menu

After the images are tiled, minimize the unnecessary windows and select TILE from the WINDOWS menu again.

Disclaimer / Feedback
Though I've hacked a few actions for my own purposes, an action expert I'm not. Suggestions, comments, problems are welecome either by posting to this thread or via Personal Mail.

Good luck...

~DannyR~

[Ed_L]

Danny,

Thanks very much for taking the time to make it available for us. I have it downloaded, but no time to try it now. Thabnks also for the description on using the downloaded file.

Ed

[jerry]

Thanks Danny

I just downloaded your "Splitchannel" action. I ran it in Photoshop 7 and it worked very smoothly. Your instructions were right on.. This is a great analytical tool for retouching. I am now going to study your action to see if I can learn about these macro's.

Thanks again for taking the time to write this and sharing it with us.

Jerry

[DannyRaphael]

Jerry...

Your kind comments and verification the .ATN works under PS7 were greatly appreciated.

I've found that a very good way to learn to write .ATNs (and bull-eeve me, I'm a rookie at it), is to download, run and dissect .ATNs written by other folks. If you haven't yet, I'd recommend checking out the Action Exchange at Adobe.com.

Some are great. Some are horrible. But I almost always learn something by slicing and dicing... not just from the "how to build a better .ATN" perspective, but how folks use Photoshop functionality I've never used (or heard of). Believe it or not I finally found an obscure, but semi-practical use for the "Plastic Wrap" filter from an action.

~Danny~

[jeaniesa]

Danny,
I also tried it on PS7 and it worked perfectly. I don't have other versions installed to try it out on. THANKS so much for putting this together - this will be VERY helpful!
Jeanie

[Stephen M]

Danny, Excellent work!

I have had problems with some of my actions with multiple docs open - but did not know why...after playing with your action I can see that this aspect needs more thought when planning the action (the key being the order of the last listed 'key' document). The order of the files is critical and can make or break an action.

I am using a PC as we speak, but the only thing I can think of that will be an issue for Mac users is the lack of the window tiling feature in versions before 7, but most of the hard work is done for them.

Once a user is familiar with the action and the document display order, the stop messages could be disabled (unchecked) so that the process is more automated.

While we are on the topic of separate channels and looking at your image in a new way...

Mac users before v7 had a little known third party plug (if they could get it) written by Thomas Knoll from Adobe for performing HSB/HSL conversions from to RGB data (since Photoshop lost the ability to work with HSB channels all those years ago). With v7, there is a new Mac and PC HSB/HSL filter. This displays the HS B/L data in composite RGB mode, so is not very good for composite views - but the channels do have some value.

LAB is great in that it separates colour from tone (red/green in the A and blue/yellow in the B) - HSB and HSL are another two colour models which also separate the colour and tonal info in an image, but in different ways to LAB. LAB is often more useful than HS B/L modes, but there can be uses for these modes in some rare cases too. For example, the H or S channel can be useful when masking some images - just as the AB can often be good for this task.

One of the foundation principles of Professional Photoshop 6 by Dan Margulis is the 'every file has ten channels' outlook - which applies to his colour correction methods as well as rebuilding damaged channels or masking (where it is easier to demonstrate). It is amazing how deep this concept can be taken. This action can help streamline the task of having a quick view of the ten colour channels, which is fantastic.

A note for users who are not that familiar with CMYK - unlike other modes which are fixed in their results, there are many variables which can affect how the particualar CMYK plates are generated (the 4th K channel offers possibilites for mixing colour which are not found in 3 colour spaces). The same colour can be created via many different mixes of CMYK values, so if you like the look of one of the CMYK channels - there is usually a way to customize this (often the K but all to some degree)...

Different GCR/UCR, dot gain for all or individual plates, total ink limits, black ink limits etc really change things. The legacy built in CMYK settings or the Custom CMYK profile generation of later versions of Photoshop offer the near infinite tweaking of these variables.

A small attempt to list some of these factors can be found here:

http://members.ozemail.com.au/~binar...T_CMYK101.html

http://members.ozemail.com.au/~binar...T_CMYK102.html

http://members.ozemail.com.au/~binar...T_CMYK103.html

Regards,

Stephen Marsh.