P3D Re: 3D realism and focus cues

[Larry Berlin <lberlin@xxxxxxxxx>]

>Date: Tue, 20 Jan 1998
>From: roberts@xxxxxxxxxxxxxxxxx (John W Roberts)  Writes:
>.........
>
>>> You mentioned real-time adjustment of interocular. Larry Berlin has also
>>> expressed interest in that. Maybe the two of you could cook up some ideas.
>>........ (Michael Kersenbrock replies........)...................
>>Maybe in a few years.  The technology, IMO, isn't quite ripe yet other
>>than for very expensive prototypes.  
>
>I've been trying to think up some kind of sliding mirror arrangement to use
>with a Toshiba 3D camcorder. I *suspect* it would be very disturbing to watch,
>at least for the first use, but it might be possible to become accustomed
>to it. And it's bound to be interesting.
>
>It will take some *big* mirrors - I sure hope second-surface mirrors are
>good enough!

*****  Other than trying to get an idea what will work, don't bother with
second surface mirrors. The double reflection is a serious problem and
degrades the image quality badly. Once you've calculated the size mirrors
you need, go to your local stained glass supply and request front surface
mirror. Some stores have them in stock for making of kaleidoscopes. The
smartest way to do this is have them cut the sizes for you. Some of this
material is very difficult to cut. It's also expensive. The clean image from
front surface reflections is very worth it!

I've heard of some stereo cameras where a periscope style arrangement was
used, so the interocular can be adjusted by rotating the periscopes
appropriately while the camera remains fixed. The image would be unaffected
by the rotation.  I guess you'd need to elevate or lower the camera
accordingly so that the vantage point doesn't seem to go up or down with the
interocular, unless that was desired.

It might be disturbing if you made a rapid change WHILE recording images. If
done slowly and with purpose, it might be quite interesting and fun, or in
some cases barely noticable. The biggest advantage is that the same camera
set-up can be used for anything from close situations to more distant scenes
without losing the sense of depth or exaggerating it, even if you aren't
recording the transition itself.

Larry Berlin

Email: lberlin@xxxxxxxxx
http://www.sonic.net/~lberlin/
http://3dzine.simplenet.com/


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