Some users have asked why the ImageWriter LQ options for reduction are 33%
and 66% only, instead of a 50% reduction as with the ImageWriter II.
The reason is this: the Macintosh screen is 72 dpi, and the ImageWriter LQ
in Best mode prints at 216 dpi. If you take the image on the screen, and do
not scale it in any way before sending it to the ImageWriter LQ (printing
at 216 dpi), the output reduction is 33% -- that is, 72/216.
If you scale this screen image by a factor of two and print it on the same
printer at 216 dpi, the result is a 66% reduction -- or, 144/216.
This is the difference from the ImageWriter II, which prints at 144 dpi.
The unscaled screen image, when sent to the printer, automatically prints
at 50% reduction -- at 72/144.
The reduction modes chosen for the ImageWriter II and ImageWriter LQ
printers represent the "natural" reduction modes for each, depending on
the printer resolution, and the way the ImageWriter printer drivers handle
bit-map printing.