From: drascic@ie.utoronto.ca (SpIke)
Subject: Re: Recommendations for 3d station?
Organization: University of Toronto, Department of Industrial Engineering
Date: Fri, 16 Oct 1992 03:13:33 GMT


lebaron@INRS-Telecom.UQuebec.CA (Gregory LeBaron) writes:

>>   One of the professors here wants to get into 3d viewing stuff. His
>>   requirements are not well defined yet but 120Hz refresh rate and 24
>>   bit colour seem to be important to him. 
>>   INRS Telecommunications, 16 Place du Commerce,
>>   Verdun, Quebec, Canada, H3E 1H6

skravis@garnet.csis.dit.csiro.au (Simon Kravis) writes:

[StereoGraphics Corp sells a stereoscopic graphics setup]
>>It's a special hardware box plus monitor and remote controlled glasses
>>that works from the RGB output. The pre-stereo image is formatted to
>>have one eye image on the top of the screen and the other at the
>>bottom, and the hardware box stretches each eye image to full screen
>>height and displays them alternately, so the interface is totally in hardware.

>>This system looks as though it loses out in vertical resolution
>>through squeezing the left and right eye images, but does give 120
>>frames/sec. We haven't yet bought one so I'd be interested to hear
>>from an established user.

Actually, the bit about loosing vertical resolution isn't that clear
cut.  Although each eye gets half the vertical resolution, the brain
can integrate the two images, and so the final image may not be quite
as degraded as feared.  Furthermore, vertical resolution is usually not
as important as horizontal resolution, to which the eyes are more
sensitive.

>>Prices are reasonable - special monitor + hardware box +
>>glasses for about $7000.


hunter@werple.apana.org.au (James Gardiner) writes:

>From what I know of the SGI stuff.  If you get a Indigo XS24withZbuffer
>No a cheap machine but, with the sterio ready monitor and lcd
>3D glasses you can see full screen res 3d images.  The screen must
>have a 120 refresh as the glasses flash and give each eye the seperate
>image at 60MHz.   This 120MHz image speed mentioned above I find hard
>to beleive.  You need the high end graphics to do double buffered
>24bit images.

>SGI should be able to do the job best but probably not cheaply.

SGI can do great graphics in wonderful real time, but if all you want to do
is display 24 bit still pictures in 120 Hz stereoscopic video (SV), then
you may be satisfied with using a PC of your choosing, SO LONG AS the
display rate of the graphics card (VGA) is 60 Hz.

Actually, it doesn't have to be a PC; it just has to have a vertical refresh
rate of 60 Hz.  (If you insist on using any other frequency, StereoGraphics
will be happy to modify their hardware to suit yours, for about US$300 per
item.)  A cheap SGI machine may do.

You can then use StereoGraphics Corp's "Graphics Display Controller
GDC-3" to "convert" the 60Hz to a 120 Hz image, and use their
"CrystalEyes" viewing glasses to look at what you are doing.  Or you
can use other glasses from 3D-TV that cost 1/15th the price to view the
same thing.  (The "conversion" isn't really anything THAT complicated; the
box simply replaces the vertical sync signal of your video signal with one
twice as fast.  Getting it done right is kinda tricky, but the box seems to
be very robust.)

(Note that the stuff Silicon Graphics sells for their machines is made by
StereoGraphics for half the price.)

You can go cheaper routes.  You may want to consider contacting

	3D-TV CORP (415) 479-3516
	- great selection of good SV equipment and tapes at reasonable prices.
	- tell Michael Starks (the proprietor) that David Drascic from the
	  University of Toronto sent you.
	
	StereoGraphics (415) 459-4500
	- limited selection of good SV equipment, pretty pricey though
	- sales creatures used to be pretty good, but lately I've been
	  very disappointed.  Try talking to Pat Lafferty, he's higher up
	  and very competent.  He may remember my name.  If he asks if the
	  cables work, tell him I'm still waiting for Silicon Graphics to
	  move it's butt! :-)

I also know that there is a company in Montreal working on medical imaging
with stereoscopic displays.  They came here to UofT to visit a while back
and showed a marvellous and awful video of brain surgery.  Ugh.  Glad I
went into engineering and not medicine! :-)  Anyway, I know that they are
marketting their stuff.  If you want, I can try to find out more information
on them.

Tektronix makes and if you are very persistent and courageous may be willing
to sell you their own stereoscopic display technology.  It will work with a
number of different computer bases.  Good luck trying to find someone to
tell you about it, though; took me 3 days of trying.

Finally, you may be interested in the:

	1992 INTERNATIONAL CONFERENCE ON 3D MEDIA TECHNOLOGIES
	Nov 2-5, 1992
	Sherton Centre, MONTREAL, Quebec, Canada
	(514) 848-2539  fax (514) 848-3492

Sessions include 3D film, 3D video, 3D projections and spatial audio,
holography and autostereoscopic (i.e. no glasses needed) displays,
and "Stereoscopic Computer Graphics, Virtual Reality, and Simulation".
I'll be presenting some of the work we've been doing here at U of Toronto
in the final session.  Also featured are:
	- opening reception at IMAX Theatre to watch 2 marvellous 3D films
	- continuous demos and displays (including MY SV+SG documentary)
	- more 3D presentations from the NFB and contributors
and the usual conference receptions.

		David Drascic
		Dept of Industrial Engineering
		University of Toronto
		drascic@ie.utoronto.ca