Example of 4-color process silkscreen with a white background. Photographic images are color-separated into 4 colors - cyan, magenta, yellow, and black. These colors are recombined on the printing press to simulate the original image.

Here you can see a close-up view 120 line screen printing. The image is a bit coarse and interference patterns from the screens appear in some areas. Those interference patterns are called moiré (pronounced mwar-ray) patterns. Moiré is always worse on CD labels because the ink is more opaque and because of the lower line screen.

Note that the copyright line above is knocked out of black ink only. Knocking tiny text out of a 4-color picture is a very bad idea because of the low line screen (100 or 120 lines per inch) and due to the inherently bad register (alignment) in the silkscreen process. See below for a close-up view of a 4 color knockout:

This is actually very good register for silkscreen. We assure you that most of our competitors would do much worse! Even most offset printers will be worse than this. But please try to avoid this kind of design.

As of May, 2001, the recommended linescreen is now only 100 lines per inch. There were just too many problems with color compensation at 120 linescreen. If you want to use 120 linescreen a different compensation curve is required. Please ask.

Films and proofs

Because of the high cost and complexity of 4-color film creation and proofing for CD labels, we let the people in the factory make the film. They know the process best. Proofing is with an electronic Acrobat file. The results have always been acceptable.

If you want to supply your own films, here is the recommended procedure:

• Generate your film positives including silkscreen compensation in the Photoshop image.
• To verify these films are good, you should make a color key or matchprint directly from these films, but you must first make negatives from the positives. This proof is not an accurate proof of how the disc will look when printed. Label this proof as "INCLUDES COMPENSATION - not accurate for color."
• Generate a second set of film negatives directly from your computer file, but this time NOT including the silkscreen compensation in the Photoshop image. From these films make a color key or laminated proof. This proof is an "ideal" of what we want off the press, and is what the pressman will try to match. Label this proof "NO COMPENSATION - Match this color."
• The process requires 13 films, 2 proofs, and quite a bit of time. It is the safest way but it is expensive.