Why do some printers use color bars with all sorts of weird color blocks and numbers in addition to the solid squares?
A.: These color bars are used to help monitor press problems and color balance in addition to the solid squares you read with a densitometer. The star targets are very difficult to print perfectly, so mechanical or chemical problems in the press are judged by the pattern of slur toward the center of the target. Some bar sets have a 40% black screen block followed by another block made up of the other three colors, which, if everything is working properly, the two blocks should look the same from a normal viewing distance. Multi-color squares are often included to indicate how well inks are trapping, both in a wet-trap or a dry trapping situation. Other components feature concentric circles or a variety of small dots and squares with numbers next to them. This helps identify problems concerning dot gain. These bar sets are the number one tool that is used to evaluate printability, and to the trained eye a great many press problems can be quickly identified to enable corrective measures
A.: These color bars are used to help monitor press problems and color balance in addition to the solid squares you read with a densitometer. The star targets are very difficult to print perfectly, so mechanical or chemical problems in the press are judged by the pattern of slur toward the center of the target. Some bar sets have a 40% black screen block followed by another block made up of the other three colors, which, if everything is working properly, the two blocks should look the same from a normal viewing distance. Multi-color squares are often included to indicate how well inks are trapping, both in a wet-trap or a dry trapping situation. Other components feature concentric circles or a variety of small dots and squares with numbers next to them. This helps identify problems concerning excessive dot gain. These bar sets are the number one tool that is used to evaluate printability, and to the trained eye a great many press problems can be quickly identified to enable corrective
