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How much do I need to know about cmyk/prepress?

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  #11  
Old 05-29-2012, 09:24 AM
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Re: How much do I need to know about cmyk/prepress

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Originally Posted by Andymania View Post
do I need to have as much knowledge about this stuff as a guy like Dan Margulis?
Nope! You only need a good ICC profile that actually defines the output process. That’s the hard part (getting that profile in many cases). The profile is the decoder ring that properly converts to CMYK from your source RGB data. You should soft proof and examine which rendering intent provides the most pleasing results (profiles don’t know squat about colors in context, humans do). The profile defines TAC, GCR, all the stuff necessary to ideally print on the device it (again hopefully) defines. There are literally thousands and thousands of differing CMYK print behaviors. Some would like you to believe you just pick any old generic profile (use SWOP V2) and all is fine. That would be true if the print conditions fully conformed to TR001 SWOP specifications that the V2 profile defines. If not, well then how far the print conditions differ, that’s how far off your output will be.
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  #12  
Old 05-29-2012, 11:00 AM
edgework edgework is offline
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Re: How much do I need to know about cmyk/prepress

I worked in a studio that had just recently begun in-house proofing. The production manager set out on a true Grail quest for correct color. He pulled some past jobs that had gone into production, and sent the files out to all the prepress shops in town, and then compared the results when he got his 15 or so contract proofs back the next day. Every one was different, of course, and he was in serious danger of melting down and running out of hair to pull out of his head, crying to the universe "Which one is the right one?" I told him, "The one that gets the client's initials in the bottom right corner." I was just trying to be helpful but it wasn't what he wanted to hear.

Profiles will get you a good distance toward your goal, but if you're looking for a way to circumvent the time-tested method of running a proof, then making subjective decisions at the light box about what to tweak, and repeating the process until the client says "That's it!" we're probably talking about a parallel universe where all inks behave the same and all proofing devices are in perfect sync. Not this universe, unfortunately.
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  #13  
Old 05-29-2012, 11:25 AM
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Re: How much do I need to know about cmyk/prepress

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Originally Posted by edgework View Post
...he got his 15 or so contract proofs back the next day. Every one was different, of course, and he was in serious danger of melting down and running out of hair to pull out of his head, crying to the universe "Which one is the right one?"
Well the first question would be, did he get 15 ICC profiles for the process? It would be easier to evaluate which is ‘right’ (the answer is nearly always, the one you prefer). And the contract proof should match the press (that’s the point of the contract proof in the first place).

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I told him, "The one that gets the client's initials in the bottom right corner."
Exactly. Now let’s hope that is what we see at the press check.

You start with the profile. Hopefully a good one that describes the process. But you have to proof. You have to get the proof signed off. Then the press has to match that proof really closely.
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  #14  
Old 05-29-2012, 11:56 AM
Andymania Andymania is offline
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Re: How much do I need to know about cmyk/prepress

Good feedback here folks. I do remember reading Margulis talking about how important contract proofs are. Andrew, you published a book on color management correct? (the one with the dog on the cover) If so, I'm gonna have to get it. Hopefully it will clear up any confusion I have on ICC profiles.

-Andy
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  #15  
Old 05-31-2012, 03:49 AM
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DJSoulglo DJSoulglo is offline
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Re: How much do I need to know about cmyk/prepress

I've recently gotten a new client who wants everything in 3 spotcolors. That was a thing I hadn't done in years. Good practise though.
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  #16  
Old 05-31-2012, 09:43 AM
edgework edgework is offline
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Re: How much do I need to know about cmyk/prepress

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Originally Posted by DJSoulglo View Post
I've recently gotten a new client who wants everything in 3 spotcolors. That was a thing I hadn't done in years. Good practise though.
Now that RIPS do their own trapping, spot colors aren't quite the nightmare in Photoshop that they once were. I remember turning my spots into CMYK proxies so Photoshop could auto trap them, but nothing short of trial and error would trap a spot color in Photoshop to an Illustrator artifact.
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  #17  
Old 05-31-2012, 09:00 PM
kav kav is offline
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Re: How much do I need to know about cmyk/prepress

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Originally Posted by edgework View Post
Now that RIPS do their own trapping, spot colors aren't quite the nightmare in Photoshop that they once were. I remember turning my spots into CMYK proxies so Photoshop could auto trap them, but nothing short of trial and error would trap a spot color in Photoshop to an Illustrator artifact.
Ugh.. that sounds absolutely terrible.

Also I agree, you never get 100% consistency with inks and papers no matter how many profiles are used to ease the process. There are just things to watch out for in terms of saturation and densities at an rgb stage. You don't want things that will obviously clip and just turn the image into a complete mess. I even check ultra saturated colors colors in raw processing. With something like a really saturated red, if you're not aware of it, you could kill detail in your red channel during raw processing, then kill it even further during the cmyk conversion. I've seen the results appear as a blob of a red dress in a magazine.

Last edited by kav; 05-31-2012 at 09:07 PM.
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  #18  
Old 06-06-2012, 08:27 AM
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Benny Profane Benny Profane is offline
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Re: How much do I need to know about cmyk/prepress

I don't get it. Why is this even a concern for retouchers? Do all of your work in the RGB space you normally work in, and just hand it off. How can you possibly know how to calibrate to the final printing process? That's for the prepress guys. And, there may be ten to thirty printing plants printing the final ad. How could you figure all that out? Well, you could, but, then you be a color management technician, which is a job all it's own. It's not retouching. And, don't let anybody tell you it is.
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  #19  
Old 06-06-2012, 08:40 AM
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Re: How much do I need to know about cmyk/prepress

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Originally Posted by Benny Profane View Post
I don't get it. Why is this even a concern for retouchers? Do all of your work in the RGB space you normally work in, and just hand it off. How can you possibly know how to calibrate to the final printing process? That's for the prepress guys.
Unless you are getting paid big time to do these conversions, and you have the stomach when things go bad on-press, I think your comments are spot on!
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  #20  
Old 06-06-2012, 09:46 AM
Andymania Andymania is offline
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Re: How much do I need to know about cmyk/prepress

Benny Profane's remark was my initial gut instinct before I started to learn all this stuff.
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