Answered by the experts at EU Services

Question:
Is there a rule of thumb about image resolution for printed pieces?

Answer:
Yes, there is! Images that have insufficient resolution will not print properly and will cause production of your project to grind to a standstill. Be sure that scanned images (as well as those from digital cameras or CD-ROMs) have a dot resolution (dpi) approximately twice that of the line screen resolution (lpi) used for printing. A resolution of 300 dpi, or twice the standard line screen of 150 lpi, is appropriate for most applications. This means that images pulled off the internet with a resolution of 72 dpi won't cut it. On the other hand, overdoing image resolution won't make a difference in print quality. Your printer's prepress system won't take advantage of any extra resolution beyond what's needed to produce an accurate line screen, and super-large image files can also pose problems when saving or transferring files.