Path: utzoo!utgpu!water!watmath!clyde!burl!codas!killer!academ!uhnix1!soma!rick
From: rick@soma.bcm.tmc.edu (Rick Gray)
Newsgroups: comp.graphics
Subject: High-quality slides from graphics terminals
Message-ID: <3286@soma.bcm.tmc.edu>
Date: 14 Dec 87 20:10:44 GMT
Reply-To: rick@soma.bcm.tmc.edu (Rick Gray)
Organization: Neurology, Baylor College of Medicine, Houston, Tx
Lines: 57

We are currently investigating ways to obtain high-quality color slides
from our Masscomp displays.  Most of our graphics uses GPS format
(created with either Masscomp Data Presentation or Creare mcplot
software, or ged output) although we occasionally would like slides or
prints from images created with Doug Logan's Masspaint program or
possibly future images obtained with a scanner.  With GPS files we have
the option of making a high resolution hardcopy, then photographing
that, but that isn't possible with bitmap files (at least we don't know
how to do it).  We already have the ability to get good-quality black &
white plots of GPS files using either: 

1) a pen plotter and drafting pens; or 
2) a filter we wrote using the Masscomp-supplied gpsras filter and a
   simplified version of their ACT color printer driver to output GPS
   files to a HP Laserjet II at 300 dpi.

We would like to minimize the amount of darkroom work required to make
color slides, since we aren't set up for color processing in our lab.  The
options we are working on now are:

1) Directly photographing the screen of an Aurora (1152x910) with a 35 mm 
   camera, using either Ektachrome or Polaroid Polachrome film.  This 
   provides pretty good slides, but it's tricky to get even brightness
   across the slide, and the image has to be reduced to ~75% to reduce 
   visible curvature.  We also have 19" (832x600) and 12" (640x480) color 
   graphics tubes, but the lower resolution only makes things worse.

2) We are working on a GPS to BGL (Business Graphics Language) filter so
   we can send files to our Medical Illustration Department's
   high-resolution slide maker system.  This looks promising, but since
   they support many different fonts, some hand editing of the BGL file
   will be necessary to get exactly what we want.  We also have to wait
   for them to make the slide and pay a healthy price for it (~$5/slide).

3) We have a Polaroid Freeze-frame Video Image Recorder as part of an
   image analysis system, but it expects either 15.75 KHz NTSC color
   composite or 15.75 KHz RGB input.  All of our Masscomp color tubes have
   a much higher horizontal scan frequency (30.86 KHz on the 12"; 32.4 KHz
   on the 19"; and 63.34 KHz on the Aurora).

So, here are our questions:

1) Is there any way, preferably through software, to slow down the
   horizontal scan rate on any of the graphics processors so we can use the
   Polaroid Freeze-frame with our Masscomps?  If that's not possible, is 
   there any way we can build a circuit to make the output compatible
   with the Polaroid unit?  [We can build practically any circuit, but 
   buying a $10K+ film recorder is not an option for us.]

2) How do other folks make high-quality color slides or illustrations of 
   data collected with their Masscomps (or any other graphics workstation)
   for presentation?

-- 
Rick Gray				uucp: {rice,shell}!soma!rick
Program in Neuroscience			arpa: rick%soma.uucp@tmc.edu
Baylor Col. Med., Houston, Tx 77030