RetouchPRO

Go Back   RetouchPRO > Tools > Vendor Support > Hidden Power Support
Register Blogs FAQ Site Nav Search Today's Posts Mark Forums Read


Hidden Power Support Support and discussion area for Richard Lynch's book and software series

Trouble Following CMYK Separation Procedure

Reply
 
Thread Tools
  #11  
Old 06-06-2003, 06:18 PM
Susan S. Susan S. is offline
Senior Member
 
Join Date: Feb 2003
Location: Adelaide, South Australia
Posts: 139
Thaks for that Richard. (Did you get my email? - my mail server is playing up again and some stuff appears to be disppearing into an electronoc black hole!)

Susan S
Reply With Quote top
  #12  
Old 06-06-2003, 08:36 PM
Stephen M Stephen M is offline
Senior Member
 
Join Date: Apr 2002
Location: Sydney, Australia
Posts: 439
Although I wrote these articles for the full version and not PSE - they are a small attempt to help explain some of the theory behind working in CMYK in Photoshop. I hope that they are of some help, please ask away if any clarification is needed on the theory, but I can't help on the actual PSE side of things.

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


Hope this helps,

Stephen Marsh.
Reply With Quote top
  #13  
Old 06-07-2003, 06:57 AM
Richard_Lynch's Avatar
Richard_Lynch Richard_Lynch is offline
Senior Member
 
Join Date: Oct 2001
Location: Western NY
Posts: 1,105
Stephen,

The problem with those articles/descriptions is that they apply to terms having to do with settings in Photoshop. None of them are available in Elements. The idea of CMYK separation and generation of color plates has to be handled entirely manually from an RGB file. Your articles and replies deal with screens and settings that don't apply at all to the Elements user creating a separation -- the terms describe things that come into play, certainly, but there is no real way to look at them as flat settings or simple considerations. CMYK functionality as you understand it and as it exists in Photoshop are not part of Elements.

The solution in Elements has more to do with the *art* of color separation as it was approached BEFORE there was digital pre-press. There isn't a CMYK mode in Elements.

One quibble with the articles, unless I misunderstood, there is a third way to separate: manual digital separation saved to a DCS file. That's what we do in Elements -- or at least it is the only way I have currently found to accomplish this, and the way it works in my book. I'd think you'd find it interesting...Quite a bit of control over the result, really, in a way you can't imitate with Photoshop's controls -- and limitations -- without using similar technique.
Reply With Quote top
  #14  
Old 06-07-2003, 09:24 AM
Stephen M Stephen M is offline
Senior Member
 
Join Date: Apr 2002
Location: Sydney, Australia
Posts: 439
Richard - I thought I made it clear from my disclaimer that the articles were written for the full version and that PSE users would need to figure out the differences as I could not help there. But perhaps not, I guess I should have been more clear. <g>

My site and the articles in question are written from a certain biased viewpoint - being prepress, which is something that I spend a lot of time doing. Many Photoshop users do not understand CMYK and that there are many 'flavours' of CMYK that one may wish to create - be it different separation types (UCR or GCR) or different targeted separations, say for coated flatsheet or uncoated web newsprint or the other variables such as reproducing the same colour on two similar conditions that use different ink - just the day to day stuff that is needed for the serious CMYK user.

Some do not understand the relation of CMY and K to neturals and colours, which I attempt to go into with UCR and GCR. There are many mixtures of CMY and K that one may wish to produce. Sometimes no or little black is wanted, othertimes more is required. Sometimes you want black in coloured areas other times only in the deepest shadows. It all depends. Again I attempt to go into this, and it matters not how the separation is created, some things are fundamental and the info is applicable to all, it is up to the user to make their tools do what is required. For example, one part mentions that more K in the sep is good for a four colour greyscale - so all the PSEHP user needs to do is figure out how to use your tools to create a separation with a heavy black plate and lighter MY and C plates (the C being a bit heavier than the MY to form a true neutral). Basic separation theory is the same no matter the tool - one just has to figure out how to perform the required edit with the tool at hand. As previously mentioned, many full version users think that CMYK is CMYK and that their are not different variables which one may use to create said CMYK. This is not helped by many in the print industry simply saying "just give me CMYK" instead of saying "give me CMYK that is suitable for SWOP TR001 type reproduction". <g>

It can be an eye opener for many that one can target different stock or ink or dot gain or other variables. Many think there is a magic 'one size fits all' CMYK space that is suitable for all uses. So some time is spent with the legacy separation controls which have fallen from favour with ICC profiles but which are still very useful. Then ICC profiles are explored, which have their own set of rules for working with them.

The reason for posting was a small attempt to bring the wider use of CMYK into focus. It is helpful to understand why one would like a certian type of CMYK over another and why one type of press may have the same image separated in many different ways. It was more about the bigger picture than the steps which may not apply to PSE users.

You are correct, due to PSE not having a CMYK mode users of PSE have a certain advantage over their full version cousins - in that they are forced to learn something for which the regular version users take for granted as being performed by a separation table or ICC profile. When it comes to spot colour work, many folk are lost as they have lost the art of creating separations - due to the fact that Photoshop handles it all for them when they do CMYK.

As the articles are written from a prepress biased viewpoint, where consistent and accurate reproduction for many output conditions is required, performing the separation as a PSE user is forced to is not even an option for most work for most users.

Full version prepress users have often manually created seps for grey, spot or CMYK - but even a die hard manual separator can't compete with the workhorse of modern separation sofware and as colour is no longer an art but a commodity there is not much profit to be made in performing manual separations. Yes it is an option, but not a serious one for most prepress settings. A PSE user using CMYK for their own sake who has the time to devote to their work can justify this. A stressed prepress operator having to separate a few hundred images in a short deadline for a crappy rate is not going to trot out PSE and perform manual seps. They are going to run a batch action or AppleScript and if lucky each image may have the K plate massaged a bit or some post separation selective colour moves applied or something quick and pleasant but nothing time consuming.

Stephen Marsh.
Reply With Quote top
  #15  
Old 06-07-2003, 09:46 AM
Stephen M Stephen M is offline
Senior Member
 
Join Date: Apr 2002
Location: Sydney, Australia
Posts: 439
In addition to this thread:

There is a way for PSE users (or anyone) to create a CMYK file using ICC profiles - but they do not need PS Elements or even the full version of Photoshop to do it!

On the Mac, there are ColorSync AppleScripts for performing _many_ ICC related tasks, including converting between profiles (such as RGB to CMYK, or more specifically say Adobe RGB to SWOP TR001 CMYK).

On the PC there is some free command line tools for this - but I have never got them to work, as I am a old Mac user and have no experience with command line operations. If one can understand the syntax that these apps use, then one can do ICC profile based transforms to TIFF files and a few other things.

Whether or not PSE can open or use the CMYK file you create with these apps or others is something else again, but as I mention there are two built in ways to separate in Photoshop as well as manually, and with Richards tools there is a manual way to do it in PSE.

Stephen Marsh.
Reply With Quote top
  #16  
Old 06-07-2003, 10:33 AM
Richard_Lynch's Avatar
Richard_Lynch Richard_Lynch is offline
Senior Member
 
Join Date: Oct 2001
Location: Western NY
Posts: 1,105
Stephen,

One should walk, or at least crawl -- or scootch -- before they run. The idea of Elements use for CMYK is that you can do it, though the manufacturer says it is impossible. Meanwhile, you learn a lot about how images perform and learn about opportunities to control output. Throwing in 100s of variables into the mix for the sake of theoretical and actual possibility is not the point or the desire -- and neither is using elements for high-volume production CMYK (pre-press professionals will probably not be seeking out elements to do CMYK work). One of my few stipulations for those needing Photoshop is that they will have to want one of these things; to work in 16-bit, to do high-volume production and CMYK, or to record actions. The suggestion is: if theere is need for a specialized professional tool for volume work, one will probably be using Photoshop. It is the justification for the cost difference.

While I think your expertise could do some good here, dismissing the tools that the Elements user has to work with may find the user confounded, overwhelmed, and confused. It is hard enough, I think, to digest the simple idea of manual separation (why CMY does NOT work for RGB). If you'd like to discuss methods of control for factors as a process in separation and as part of using the available tools (not merely saying "Adjust for dot gain.") this would prove more valuable. You do not have dot gain settings, you do not have transfer functions, you cannot embed profiles (in these images), you do not have GCR or UCR settings. The black is generated from a combination of saturation and luminosity masking, and while this can deliver very fine control of all aspects of the final result, tossing in these terms is really meaningless in the context of the interface. How they can be calculated in terms of using image information with curves, masking and calculations (or other functions) would be germane.
Reply With Quote top
  #17  
Old 06-07-2003, 09:32 PM
Stephen M Stephen M is offline
Senior Member
 
Join Date: Apr 2002
Location: Sydney, Australia
Posts: 439
Thanks Richard, I understand the intention and that you have come up with a nice way to work around a limitation of Elements that can be helpful to some users and situations.

Yes, PSE will not be the first thing a prepress user will look for - but having a stripped down version of Photoshop is something prepress folk would like, with features targeted to them and throwing away all the other unwanted deadwood, so there is nothing wrong with a less featured product in my eyes. It is not the amount of features, but what they actually are and how well they are implemented that concerns me. I could care less how well audio annotation works in Photoshop, I have no use for it. <g> But the USM filter interface and results are a big concern.

I mentioned PSE and manual seps because you said that is the only way to create seps in PSE and that I had neglected it as an option in my articles aimed at full version CMYK users - my point was that one could use PSE or the full version to manually create seps too, but most CMYK users do not have the time or budget to manually perform tasks that have been automated to high degrees of accuracy and repeatability. Yes it is a valid option and is still performed by some folk today who have Photoshop, but not for the majority of users or work in settings where press output is concerned. The separation methods listed in my article were in context to that situation but not to elements, which I originally noted before the links were supplied.

I do not think I have dismissed the tools or PSE out of hand, but for some specific work it would not be ideal, as you have noted. Manual seps may not be what a full version CMYK user would ideally choose - but that is not to say that there is no merit to them or that they may not be very useful to some folk. Being forced to manually separate CMYK would help many users - including me. But that is not going to happen at my day job, but it would be a nice exercise for play time in Photoshop.

If a PSE user is going to make their own CMYK seps, and their intended use is commercial printing - then they are going to be confronted with terms that do not apply to PSE, unless the printer is doing the conversions from RGB for them (which would be a good idea). Photoshop did not invent most of the terms or needs of press and prepress, it just responds to them (many of the terms predate digital separation).

So, with luck a PSE user that knows that there are such terms as GCR, UCR, grey component, total ink limits, dot gain and other jargon may be able to look at what factors are needed for successful CMYK generation and may then further research what these functions do and if they can/should be emulated with the tools that PSE offers.

The reason for posting the article links was to add to the general topic of CMYK, more so than the tools used to get there. In my earlier post I did mention that I was more than happy to expand on the theory behind CMYK so that a PSE user could try to translate that into their tools. The offer still stands, but without direction I can only use the current three articles that I previously pointed to for explaining some of the things that affect CMYK generation/use.


Stephen Marsh.
Reply With Quote top
  #18  
Old 06-09-2003, 12:44 AM
Jeff F Jeff F is offline
Junior Member
 
Join Date: May 2003
Posts: 28
Thanks, Stephen, for posting the links to your articles on CMYK. They're very well written and informative, and I think I absorbed quite a bit from them. It would appear that CMYK separations provide much more control than I am ready for. It must be akin to piloting an airliner. Most business travelers would probably like to have more control over their itinerary, but I doubt that flying in the captain's seat is what they would have in mind. I'm afraid that I will be relegated to a passenger seat for the time being while my print drivers do the flying.

However, that's not to say that I'm not fascinated with the subject. I'd very much like to hear from anyone using Richard's method of CMYK separations for printing on a home inkjet printer to understand the control they're looking for and how well they have been able to achieve it. Have you noticed any distinct advantages or disadvantages?

Thanks,
Jeff
Reply With Quote top
  #19  
Old 06-09-2003, 06:18 AM
Richard_Lynch's Avatar
Richard_Lynch Richard_Lynch is offline
Senior Member
 
Join Date: Oct 2001
Location: Western NY
Posts: 1,105
Jeff,

As I was trying to say -- and my worries about Stephen's posts -- there is no reason to get scared off...

While there can be a lot of complications, if you follow what's in the book (or use the tools!) you can easily try it without adjustment from what I've preset. If the result is not to your liking, there are ways and means built into the process as I've set it up to allow you to adjust the result.
Reply With Quote top
  #20  
Old 06-09-2003, 02:14 PM
Jeff F Jeff F is offline
Junior Member
 
Join Date: May 2003
Posts: 28
Hi Richard,

In all fairness to Stephen, I don't believe that anything I've read from him has scared me off of CMYK. I had reservations about the utility to me of that particular separation before Stephen chimed in. That's why in my last post I ellicited some anecdotal experiences from other users on how they're using your procedures to their advantage when printing from a typical inkjet printer. Unfortunately for me, I have still not reached the printing chapter of your book (I'm now on chapter 7), so I have not had a chance to play with it yet. Perhaps I should hold any other questions on this subject until I have reached that chapter and have played with the prints. Many of my questions may be answered there.

Thanks to you, Stephen, Susan, and everyone who take the time to share experiences and opinions with amateurs like me.

Jeff
Reply With Quote top
Reply

  RetouchPRO > Tools > Vendor Support > Hidden Power Support


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
3D skill, motion graphics skill, design skill, and now CMYK? benzilla Work/Jobs 0 02-07-2007 04:20 AM
Problem in CMYK separation procedure pps 143-144 geomouchet Hidden Power Support 1 09-04-2005 09:04 AM
CMYK Separation engineerbob Hidden Power Support 1 04-03-2005 08:02 AM
CMYK Separation as TIFF? Shotster Hidden Power Support 6 02-13-2004 12:53 PM
problems w/ CMYK chapter dpnew Hidden Power Support 6 01-22-2004 01:51 AM


All times are GMT -6. The time now is 03:08 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
SEO by vBSEO ©2011, Crawlability, Inc.
Copyright © 2016 Doug Nelson. All Rights Reserved