T3D Fw: Computer graphics 3D projection methods...

["gl@xxxxxxxx" <gl@xxxxxxxxxxxxxx>]

('tech' might be a better place for this...)

Hi there,

I'm new here.  I joined not only because I've had a massive fascination with
all things 3D for a long time, but more specifically because I'm looking to
get a wall-sized 3D projection system working for my own computer based 3D
project.

Initially I researched all the 3D projectors out there, and really liked the
VREX for being able to show non-flicker, non LCD shutter 3D (I'm highly
sensitive to flickering and have never been satisfied with LCD shutters for
that reason, plus the weight and arkwardness of shutters tends to destroy
immersion for me).

So anyway, as polarised projection is clearly the way to go for me, I
requested the VREX price list - and whinced!  As I have no external funding,
the question then was how to do this cheaply.

I've now got two options - use two second-hand LCD data projectors, or two
CRT based graphics-grade projectors, polarising each of their outputs and
overlapping their images (although if anyone has a second-hand VREX for sale
let me know).

Now, bear in mind that I've never actually seen either of those two in
action (in a stereo config or otherwise), so I'm going exclusively by my net
research.

The LCDs I'm looking at are some used 800x600 capable Telex P400 @ 400 ANSI
lumens.  Pluses are cheap, portable, downsides are lamp cost and low
resolution.

The CRTs I've got my eye own are the Electrohome ECP 4101's, 1280x1024 @
150ANSI (600 peak).  The resolution is excellent here, and I'm told that
although the ANSI figure suggests a much darker display, in actuality, due
to the differences in technology, the average video type scene will actually
be brighter on the CRTs, whilst a full white screen would be significantly
darker (but not very usual).

Anyway, if anyone here has experience with either technology (or even one of
those specific models), I'd appreciate your feedback on them.  Also, if
anyone has tried to configure two projectors this way, perhaps you could
share your experiences - what kind of polarisers did you use, how much can I
expect to pay for them for either system, what kind of screen (or did you
use an aluminium-painted homebrew?), what was the 3D effect like, how does
it compare to an all-in-one VREX projector (which I gather some of you seem
to have seen in action, according to the archives) etc.

BTW, I'm UK based.
--
gl