These guidelines should help you submit art that will print well. Color separation and printing do not improve bad pictures, so try to send us your best. In most instances, negatives reproduce better than prints. Electronic files are optimal, of course. Note that electronic manipulation of color files imposes a color shift, based on the algorithm used to convert from RGB to CMYK color.
Contrast is very important.
Different areas of color need to have sharp edges to reproduce well, unless you are trying to show soft gradations of color. Areas of color without sharp edges will probably print a bit muddy. They need more contrast. Conversely, very light pictures, such as light blues and pinks against white, also do not print as well as higher contrast pictures. Dark pictures will get darker, since the printing process involves dot gain, where the ink spreads on the paper.