Newsgroups: comp.lang.postscript
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: compensating for distortion
Message-ID: <1990May31.001233.9322@utzoo.uucp>
Organization: U of Toronto Zoology
References: <90May30.095014edt.18974@me.utoronto.ca>
Date: Thu, 31 May 90 00:12:33 GMT

In article <90May30.095014edt.18974@me.utoronto.ca> sun@hammer.me.UUCP (Andy Sun Anu-guest) writes:
>I tried to print a perfect square on an Apple LaserWriter II NT ...
>But the square that I got was distorted. It is approximately 0.5 mm longer
>in the y direction (11" direction) and 0.5 mm shorter in the x direction
>(8.5" direction). It is essential for us to get an undistorted printout.
>
>Does anybody know what is the reason for this? ...  Is it
>because of the aspect ratio (does a laser printer have aspect ratio?) of the 
>laser printer? ...

Almost certainly that's the cause.  Most "300dpi" laser printers are in
fact something like 298dpi on one axis and 303dpi on the other.  Usually
the manufacturers don't even bother telling you about this, much less
provide a way to compensate for it.

(This isn't unique to laser printers, either:  most photocopiers likewise
have slightly different X and Y axes.)
-- 
As a user I'll take speed over|     Henry Spencer at U of Toronto Zoology
features any day. -A.Tanenbaum| uunet!attcan!utzoo!henry henry@zoo.toronto.edu