Using RGB (red, green, blue) when designing for print is one of the worst No-Nos a designer can make. And it puts the printer in a very difficult position.
As a printer we have several options.
1: Return the file to the designer
2: Convert the file using Pitstop
3: Convert the file using Acrobat
4: Convert the file when we rip the file
5: Export all the RGB data to Adobe Photoshop and covert it to CMYK
Unfortunately options 2-5 may have undesirable results. Each of these option may not produce the RGB color accuracy that the designer or the designers customer/editor/publisher may have intended. Every prepress program uses a different color conversion engine and or profile converter, including Adobe Photoshop. In addition, the RGB color space has a larger color gamut than does our press cmyk gamut. Red and Greens get clipped in cmyk. Black type and black fills will convert to CMYK black (high percentages of cyan, magenta, yellow and black). Any misregistration on press will appear ans blurry type or filled in reverse type. Option 5 is time consuming and can be considered a chargeable AA.
So as a printer we ask our friends to verify that all text and images be checked in Adobe Acrobat prior to uploading the files to us. In addition, if pages are black and white it would be a good idea to convert them to black and white prior to sending them to us as well. We all want to achieve expected results and these tips may help you get their.
To check you color in Adobe Acrobat without pitstop. Open the file in Acrobat. Go to the "Advanced" pull down menu, "Print Production", "Output Preview". Select the "show" rgb. If your file has rgb data it will display in the file. Change to "show" cmyk and Acrobat will show just the cmyk data. View the sample images below. If you have determined that the file has RGB data go back to your layout program and fix the RGB.