Microsoft KB Archive/67977

Lighter Colored Lines Don’t Print on LaserJet Printers PSS ID Number: Q67977 Article last modified on 10-29-1991 PSS database name: W_PowerPt

2.00

WINDOWS

Summary:

PowerPoint’s narrowest style of line will sometimes not print on the LaserJet family of printers when you print at 75 dpi. This occurs when the line is colored a light shade on a white background, or a dark shade on a black background.

More Information:

This problem occurs because it is impossible to dither single-pixel width lines. At 75 dpi, a single-pixel width line on the printer is equivalent to a single-pixel width line on the typical video display. A typical VGA system can display 16 different colors without dithering, but the LaserJet can only display either white or black without dithering. Dithering (using patterns of solid-colored dots) is how the LaserJet printers create the appearance of different shades of gray. No matter what color you choose for a single-width line, the LaserJet will print either black or white. For this reason, lines of a lighter shade will appear to not have printed if the background also is white.

Copyright Microsoft Corporation 1991.