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From: des@yatton.inmos.co.uk (David Shepherd)
Newsgroups: comp.lang.postscript
Subject: Re: Different printers - different output
Message-ID: <1733@brwa.inmos.co.uk>
Date: 31 Jul 89 08:49:03 GMT
References: <848@tundra.misemi>
Sender: news@inmos.co.uk
Reply-To: des@inmos.co.uk (David Shepherd)
Organization: INMOS Limited, Bristol, UK.
Lines: 22

In article <848@inmos.co.uk (Terry Lalonde - iccad) writes:
>I have a postscript program that produces different output on
>two different postscript laser printers (an APPLEWRITER(SUN) 
>and a dataproducts LZR2665).  The image originated as a SUN
>bitmap, was imported into FRAMEMAKER and was printed.
>
>The image comes out very faint on the Dataproducts (~$25K)
>printer and comes out as it should on the apple (<$5K).

The AppleWriter is a write black printer while I expect from the
problem that the Dataproducts is write white. Each printer will have
its internal pixel generator for text tuned for its print engine -- hence
text looks correct on both, but for bit maps you notice the difference.

I don't know if anyone has a simple solution for printing bitmap
images --- the software that generated the bitmap image may have parameters
that can be changed to produce write white images. This is what has to be
done when generating pixel maps with METAFONT for TeX fonts -- you need
one set of pixel maps for write white and one for write black ;-(

david shepherd
INMOS ltd