Begin with the Best Art. Despite advances in graphic software and printing, the adage “Garbage in, garbage out” still applies. The better the original, the more latitude the printer has in achieving desired results. Use photographs that exhibit full tonal range. Don’t convert a color photo to a black-and-white reproduction, if a black-and-white original is available. Start with the best, each step results in a generational loss in quality.
Use the Right Software. Prepare your art in the program best suited for the task. Illustrator is a drawing (vector) program, ideal for logos, packaging, posters and single-page layouts. Photoshop® is a pixel-based (raster) program for size adjustment, color-correcting and manipulating scanned images such as photographs and flat art. Neither is intended for multi-page documents. Use a page layout program such as Adobe InDesign for multipage documents.
Make Image Changes Before Importing. Scale, rotate, flop and manipulate images in the original graphic application (Photoshop or Illustrator) before importing into your page-layout program (Adobe InDesign). If done in a page layout program, these steps consume computer memory and may cause output difficulties.
Maintain Image Quality. Photoshop® provides tremendous pixel control, keep in mind that raster software does not enlarge images without a loss in quality. When producing a digital image, start big, you can scale down later with impunity. If you need to enlarge an image, rescan or reshoot at a higher resolution.
CMYK or RGB. Remember that offset printing requires all files be in CMYK to separate properly. Printers often prefer to make the conversions themselves to stock images supplied in RGB mode. If the printer requests otherwise, ask for a conversion profile to follow. Keep in mind that standard default settings on your software may convert some colors to straight black, rather than build the color out of CMYK.
Trust the Software, Not the Screen. If you are doing color corrections or manipulations on your own, rely on the numerical color gauges in Photoshop® rather than what you see on the screen. Be sure to color calibrate your monitor and printer to reduce discrepancies.
Keep Track of Your Colors. Graphic programs give you an infinite choice of colors, you may want to test out different hues to see which works best. Be sure to keep track of colors and eliminate any unused ones before releasing files. Otherwise, you may end up with a separate match-color plate for every color tested, or you may accidentally specify four-color process for a job that should be printed only in match colors.
Build to Size. Build your files at actual size unless your final size is too large for your software to accommodate. A printed piece with a final size of 8.5 x 11 should be built to 8.5 x 11 page size. Spreads should be created as two 8.5 x 11 pages, not as a single 17 x 11 form. Before releasing, add 1/8th inch bleeds where appropriate and be sure to indicate this. Allow your printer to make adjustments for crossovers, gutter grind-off, creep, etc.
Name Your Files Clearly. Unusual characters in a name have been known to cause a printer’s computer to crash. Keep file names under 20 characters and use letters and numbers only. Make sure your files are labeled with the correct extension: .ai or .eps for Illustrator; .tif or .eps for Photoshop; .indd for InDesign and .pdf for PDF. Important: Indicate which software version you used in preparing the fileecause as some printers may not have the latest versions.