Blue printing Purple on 4-Color Process Newsprint
I work for a printing company and we receive all kinds of files. The color blue has always been a problem when it prints in 4-color process (CMYK) on the press. Depending on the color, it will print purple or turquoise. Any advice on controlling this color when I don't have the layered file or I am working with a PDF.
User login
Navigation
Latest critique
Active forum topics
Can you alter your inks or
Can you alter your inks or bring the pdf into PS and alter channels?
The only problem with that
The only problem with that is the file is not layered and I only need to change the background and not the objects on top.
Find out what blue works and
Find out what blue works and then tell that to the designer who sent you the file. Then figure out why your printer isn't printing blue correctly. I wonder if you're being sent files with rgb jpgs for images?
In any event, communicate with the originators of these files and make sure they are following your procedures.
----
Natobasso
dirtandrust.com
"Powerpoint is not a design application"
Can you bump up the blue
Can you bump up the blue (Cyan) on your press?
----
Natobasso
dirtandrust.com
"Powerpoint is not a design application"
is this an issue on press or
is this an issue on press or an issue on a digital printer?
if it's on press, your press operator needs to make sure that his press is reproducing the same blue that you are getting out of your proofing device. that's an issue that most designers wouldn't know how to fix (i know i don't).
if it's digital, as in copier or nexpress or something like that, that could be a slightly different issue. you probably have some issues with color management profiles if it's too far off. and, in my experience, digital devices often have problems printing accurate blues, particularly if it's coming from an RGB source.
in particular, microsoft products (word/ppt/excel) are notorious for having blues turn out purple on digital devices. there's just something about how the RGB values in MS products are converted to cmyk that make that a difficult color to hit right.
Can you post the PDF?
Can you post one of these PDFs online so we can take a look at it. It's highly likely that the color was created in the RGB color space, or the profile isn't the proper one for commercial printing presses. Either way, seeing the PDF will shed some light on the problem.
-----------
Visit The Graphic Mac for graphics and Mac OS tips, reviews, tutorials and discussion.
Agreed. Can you post the
Agreed. Can you post the pdf?
This is really a situation where the actual file will dictate the solution. If you can crack the pdf open with no consequence in Illustrator, then you can probably change the background to a color that will print properly on your press.
many things it could be
as a prepress guy myself, If it has always happened, then it can't be the file, though it could be that if you are color-managing, YOUR color profile may be set-up incorrectly. so if you do color manage, be sure to have it recalibrated. we used to check our presses and platesetters once a year, but it was part of our service contract with Kodak. Generally, if it looks OK on screen, it's probably NOT a color management problem, but to be sure try turning it off if (it's on), or on (if it's off)
we never color managed... and we discarded customer color profiles if we got them because they almost always screwed up our internal system. We adjusted on output if needed.
Which workflow are you using? I used to use Prinergy.
your issue sounds more like it could be a press or an "output curve" issue to me, as though someone adjusted the magenta curve for a specific job and forgot to set it back to a preset for normal work again. so if the color management trick doesn't work, check the output curves.
since presses have the most gamut limitations, we always worked backwards from the press... our proof printers were calibrated to print as close to the press as they could, and screen colors didn't matter because we went by values not by visuals. the customer then approved the physical proof and that's what we color-matched to on press. PDF and laser proofs were for content only, the Creo Veris Proofs were for color matching.
just to be thorough...
if it was the press, it would be all tones of magenta that were heavy, not just the shadows. If it's over-inking, your shadows would be plugging from dotgain, but you'd also see it in the registration marks on presssheets (the ones that look like many fine lines radiating from the middle, and the crosshairs) if these marks arent on there, they should be, they're for determining these problems.
It's probably not the plates or plate processors, because then all plates (all colors) would be off by the same amount.
Try Kodak's GUA foums: http://www.myguaforums.org/forums/index.php
Yes, I know what you're talking about.
Blues turning purple on press have long been a prepress problem from the days of MatchPrints. Newsprint has presented a special challenge since nobody bothered to create a device calibrated to SNAP standards. That is, until Inkjet proofing became a reality.
Today, things are a bit easier thanks to color management and inkjet proofers and I'll show you how you can eliminate this problem once and for all.
First, if you recognize that American Newsprint typically runs TVI 27-35% and TAC 240, then you realize that you'll need to create the appropriate separation for your output. That's step one. Step two is being able to create appropriate proofs.
First, you'll need a SNAP (not SWOP) profile loaded into your system. Download one here and place the unzipped icc profile into your profiles folder (Mac_3a:Users:kevin:Library:ColorSync:Profiles:).
http://www.snapquality.com/uploads/SNAP-2007_ISO.zip
Next, open a PDF where you expect the blue to turn purple and select Advanced -> Output Preview. You'll notice a pull down menu that says "U.S. Web Coated (SWOP)" and that the blues look nice and blue. Now, select SNAP 2007 in the pull down menu and you should see the blues turn purple!
Thats a good thing. That means we can fix it.
If you get that far and see what I describe, send me an email and I'll get you the rest of the way. Have to run now.