Sometimes we feel like we’re a broken recording that plays all day, every day, the same line: Please save your files in CMYK with 1/8” bleeds and cut marks. It’s not too much to ask, right? Well maybe it is for some designers and the lesser experienced people who are tasked to create something for someone or themselves. I won’t bore you with the details, others have already gone to great lengths to explain the difference between CMYK and RGB color space. The sole purpose of this blog is to state in very clear terms, we need you to save your files in CMYK with 1/8” bleeds and cut marks if you want your file to print accurately and to avoid several back and forth phone calls and emails.
Here it is. If you have ever owned a color desktop printer and needed to go buy those expensive little color cartridges, you may already know this. For everyone else, here’s why. Our presses (and everyone else’s for that matter) use 4 basic ink colors to generate a spectrum of color. These four colors are CMYK. This stands for Cyan, Magenta, Yellow and the K stands for Black. The colors in your digital file are going to be interpreted by our presses using only those 4 colors. We don’t have a pink or green or purple or orange ink cartridge. The appearance of those colors is done by mixing the CMYK values and reproducing tiny little dots that either overlap or touch one another. Not all colors in the spectrum can be reproduced in CMYK. Those colors are considered to be “out of gamut”. We ask you to convert your RGB colors to CMYK so you can have a peek on your monitor (however poor the calibration is) of how the RGB images are going to change once you save your files in CMYK
Yes, it’s possible to expand the limited CMYK color gamut on some machines. Our wide format printer, that makes posters and banners, has 2 additional units that help us do this. But the basic production presses and digital presses don’t have this option. So help us to help you get your job finished quickly without any unexpected results and save your files in CMYK.
If you forget or decide it’s too difficult to figure this out, have someone perform this crucial step. Otherwise, your colors will not print as they looked on your monitor. This is because there isn’t a press that uses RGB inks (which stands for Red, Green, Blue) There is no such thing. RGB is what your monitor uses to present color. It’s how monitors were designed from the start. So what happens is this, our digital presses see the RGB file during the processing stage. Now unfortunately, our presses do not have alarm bells or RGB recognition brakes that say STOP, I’m about to reinterpret your RGB colors into CMYK. They just do it and make the requested number of copies, automatically converting RGB to CMYK using software that you may be OK with, but usually are not. It just depends on how color critical your job is.
There’s 2 quick ways to avoid all this. The easiest way is when you save your file as PDF. Go to your Acrobat controls and choose “Press Ready” or “PDF-X1A” for the preset. Either of these will convert your RGB colors to CMYK during the conversion process to PDF. Then look at the PDF file that was created before submitting and compare this to your original file to see how colors may have shifted. The 2nd way, if you’re using a decent image editing program, is to design in CMYK color space or convert the file to CMYK in the final stages of development