HP Color LaserJet 4500 Printer series - Manual (Page 160)

160 Solving Problems with the Printer EN
Dull or dark colors on transparencies
Problem Solution
You are using transparencies that do not meet
the media specifications for this printer. Use only transparencies that meet the
specifications for this printer (see chapter 3).
The selected colors are undesirable when
printed. Select different colors in your software
application or printer driver.
Spots and smudges appear in the background
areas of transparencies when they are
projected. Oil from your hands can cause spots or
smudges on transparencies. Reprint the
transparencies, being careful not to touch the
surface of the transparencies.
You are using a reflective overhead projector. Use a standard overhead projector.
Rippled or wavy transparencies
Problem Solution
You are using transparencies that do not meet
the specifications for this printer. Use only transparencies that meet the media
specifications for this printer.