RGB vs. CMYK

There are two worlds of color in the computer and printing industry. There is RGB (red, green and blue) and CMYK (cyan, magenta, yellow and black).

RGB is composed of the primary additive colors of red, green and blue. When red, green and blue light is combined it forms white. Computers generally display RGB using 24-bit color. In the 24-bit RGB color model there are 256 variations for each of the additive colors of red, green and blue. Therefore there are 16,777,216 possible colors (256 reds x 256 greens x 256 blues) in the 24-bit RGB color model.

RGB appears brighter on a computer monitor because its compsure is made of light.

The CMYK printing method is also known as "four-color process" or simply "process" color. All colors in the printable portion of the color spectrum can be achieved by overlapping "tints" of cyan, magenta, yellow and black inks. (A tint is a screen of tiny dots appearing as a percentage of a solid color.) When various tints of the four colors are printed in overlapping patterns it gives the illusion of continuous tones, like in a photograph or a postcard.

The CMYK model forms its gamut from the primary subtractive colors of cyan, magenta and yellow. When cyan, magenta and yellow inks are combined it forms black—in theory. However, because of the impurities in ink, when cyan, magenta and yellow inks are combined it produces a muddy brown color. Black ink is added to this system to compensate for these impurities.

This is why CMYK appears darker than what is perceived on a computer screen.

Image Resolution

After color, another main concern in printing is image resolution. Resolution is defined as a pixel count in digital images. Pixels are the little squares of color that make up an image. The computer screen can view resolution at 72ppi* (pixels per inch). That makes great for web images. However, print resolution is somewhat different.

The most typical print resolution is 300dpi** (dots per inch—as discussed above how color ink makes dots that overlap). If a picture that was 72ppi is converted to 300dpi and increases size, the picture will take on a very blotchy look. That is because the small squares of color have also increased in size, but there is no detail. This is what happens when we take a web image and make it larger for print. The detail is lost and the image prints poorly on the press.

We may request that you send us original artwork, so that your design piece has the best quality of printing before we send it to press. Unfortunately, if the quality of the image is low, so will the print, because of loss of detail, we cannot reproduce the image to be crystal clear. If you would like us to scan some artwork for you, there may be an additional fee depending on the quantity of images you would like to have scanned.

*ppi – pixels per inch. Measurements used by scanners, digital cameras and computer screens.
**dpi – dots per inch. Measurements used by printers and printed pieces.

If your image quality is bad and you insist on the use of the image, we may ask you to sign a waiver as we are not responsible for the print quality. Although we strive towards full customer satisfaction, the final choice and okay to print is the customer's responsibility. For any other printing questions, please contact us and we will be happy to assist you.