Re: 3D Video

[P3D Bill Costa - UNH Computing & Information Srvs <W_COSTA@xxxxxxxxxxxx>]

    P3D Andrew Woods <andrew@xxxxxxxxxxxxxxxxxxxxx> recently wrote (in
    part):

>    There are three types of 3D Video tapes I have heard are on the market
>    -  they are (1) pulfrich (2) anaglyph and (3) field-seqential (uses LCD
>    shutter glasses). 

    ....and....

> The Best and most effective technique is number 3.  Full colour 3D images
> albiet with some flicker.  

    An excellent explaination of the currently available technology!

    I would add only that another way to view field-sequential is by using
    a suitable Head Mounted Display (HMD).  I bought a pair of the Virtual
    I.O i-glasses which are primarily marketed for use with computers but
    are in fact NTSC field-sequential video compatible. (For computer use,
    they provide a VGA to NTSC adapter).  I opted for a HMD because I
    guessed that there would be less flicker, and based upon what I have
    seen, I was right.  (On the other hand, hi-end shutter glasses, like
    those used with SGI computers run at 120hrtz, don't flicker either, but
    since those are not compatible with NTSC 3D tapes, at least not without
    some expensive hardware, it's a moot point.)

> Generation of 3D video is usually done with a pair of genlocked video 
> cameras and a 3D multiplexer.  The multiplexer receives the input of the
> two video cameras and outputs a field-sequential 3D video signal.  It is
> basically just a very fast switch which selects odd fields from one
> camera and even fields from the other camera.  The output can then be
> recorded on a standard VCR or viewed directly on a monitor.

    It's been over a year since I bought my HMD, the next purchase was to
    be a pair of cameras and a multiplexer.  What has stopped me is the
    cost of the gear and the lack of guarantee of success.  A multiplexer
    for genlockable cameras can be had for a reasonable price, but then 
    the cameras themselves are hard to find and expensive.  On the other
    hand cheap color CCD cameras are easy to find, but a "infinite-window"
    multiplexer that can handle them is very expensive.  *sigh*  I also 
    know of at least one source for a complete, ready made  3D camera, but
    at over $8K it is hard for me to shell out the money.  $2-$3K for a
    toy that may end up sitting on the shelf is one thing, $8K is getting
    into serious money! ;^)

                                                        Later....BC

##    ##    ##    ## +----------------------------[ Bill.Costa@xxxxxxx ]---+
##    ###   ##    ## | Bill Costa                                          |
##    ####  ##    ## | CIS - Kingsbury Hall                                |
##    ## ## ######## | 33 College Road              PHONE: +1-603-862-3056 |
##    ##  ####    ## | University of New Hampshire    FAX: +1-603-862-4778 |
##    ##   ###    ## | Durham, NH  03824-3591  USA                         |
 #######    ##    ## +----------------[ No good deed goes un-punished. ]---+


------------------------------