Offset Printing Guidlines
General Offset printing CMYK Guidelines
There are several guidelines that apply to all design applications. Keeping the following guidelines in mind before you begin will help you start right and save time and money when you project hits production.
Bleed refers to the overlapping of the art past the edge of the trimmed piece. It is physically impossible for any cutter or trimming device to cut perfectly to the edge of the art. Having bleed eliminates the risk of getting white edges along your finished piece. You must included at least .125 inches of bleed (1/8″) on any element that extends to the edge of your artwork. Also, you want to maintain a margin on any text or art you do not want trimmed at least .125 inches in from the edge of your art. A larger bleed or margin may be required on more complicated items such as booklets and pieces with multiple folds etc.
Fonts (the actual font files) need to be including when submitting any (layered) job.
ie. Adobe Illustrator, In-design.
Images should have a resolution of at least 300 dpi. at the printed size for offset printing and need to be CMYK using Web Coated SWOP ver. 2 profile. image. If you are working with RGB images, the best practice is to first convert the images to Adobe 1998 RGB before converting to CMYK using the Web Coated SWOP ver. 2 profile. You will get the least amount of color shift this way. Also,converting directly from another RGB color space to the CMYK – Web Coated SWOP ver. 2 space will yield different color values..
Black is always specified, by default to overprint. Therefore, if you don’t want to see images or backgrounds through your black elements, you need to create a “rich” black – usually 30 cyan, 30 magenta, 30 yellow, and 100 black. This will give you a much richer/darker black as well as knock out any under lying objects.