Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!comp.vuw.ac.nz!actrix!Bruce.Hoult
From: Bruce.Hoult@bbs.actrix.gen.nz
Newsgroups: comp.lang.postscript
Subject: Re: Halftoning Algorithm
Message-ID: <1990Nov26.004917.9053@actrix.gen.nz>
Date: 26 Nov 90 00:49:17 GMT
References: <1504@cluster.cs.su.oz.au> <7344@hub.ucsb.edu> <1990Nov23.134554.24723@jarvis.csri.toronto.edu>
Sender: Bruce.Hoult@actrix.gen.nz (Bruce Hoult)
Organization: Actrix Information Exchange, Wellington, New Zealand
Lines: 11
Comment-To: avi@dgp.toronto.edu

In article <1990Nov23.134554.24723@jarvis.csri.toronto.edu> avi@dgp.toronto.edu (Avi Naiman) writes:
> Actually, contrary to popular assumptions, CRTs also suffer from this
> spatial non-linearity.  The average intensity of a checkerboard pattern
> of alternating black and white pixels will usually be darker than the
> mean of the black and white levels (see, for example, [Mulligan and
> Stone 89]).  In my work, I have found monitors on which the
> space-averaged (normalized) luminance of a checkerboard is as low as 0.2,
> rather than the expected 0.5 [Naiman 90].

Do you happen to know how bad/good the standard Macintosh b&w display is in
this regard?