gray levels
- To: mathgroup at yoda.ncsa.uiuc.edu
- Subject: gray levels
- From: karl at park.bu.edu (Karl Frederick Arrington)
- Date: Mon, 25 Feb 91 12:00:31 -0500
I am running: Sun-4 (SunOS) 1.2 (November 6, 1989). I would like to
draw an image with at least 256 gray levels, but I only seem to get 32
levels, which looks like luminance steps rather than a smooth ramp. I
remeber being able to change (increase the gray range of) the color
map for Mma on the Mac, but haven't figured out how on the Sun-4. I
tried it w/ and w/o (1) $AlwaysUsePrivateColorMap = True; and (2)
{PlotColor -> False}, but this still only provides 32 levels, even
though I'm specifying many more levels:
$AlwaysUsePrivateColorMap = True;
tg = Flatten[ Table[ { GrayLevel[n/10.0], Line[{{n,-1},{n,1}}] },
{n,0,10,0.025} ] ];
Show[ Graphics[ tg ], {PlotColor -> False} ];
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Karl Frederick Arrington Private: 617-353-6181
Center for Adaptive Systems Office: 617-353-7857
Cognitive and Neural Systems Program email: karl at park.bu.edu (ARPANET)
Boston University
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