[geeks] paint that retains polarisation?

[Francois Dion]

On Fri, Sep 26, 2008 at 1:53 PM, Francois Dion <francois.dion at gmail.com> wrote:
> But back to my original question. I'm looking to retain as much of the
> light polarization as possible. Why? For 3D.
>
> I have a mirror splitter/combiner in front of the projector, using 4
> mirrors, and in front of that, a pair of linear polarizing filters.
> One at 45, the other at 135 degree. I have the matching 45/135 glasses
> with a metal frame, aviator style, same type of polarization as IMAX
> theather. This is different than the Real D system which uses circular
> polarization, but it is the same concept.
>
> I feed the projector from my HTPC, with mplayer displaying the movie
> in an over/under setup, so my mirror setup is vertical. The external
> mirrors are aligned so that the two images are superimposed. Up to
> now, all is good. But the paint on the wall doesn't retain enough of
> the polarization and it is ghosting way too much.
>
> Francois

Contacted Behr and they replied that they dont have polarization
retention as data for their paint. Not surprising. For now I'll use a
retractable silverscreen (da lite, from a bygone era). It is smaller
than what I wanted (about 65" diagonal fully extended but about 54"
usable in cinemascope ratio) but it'll do for now.

BTW, Panasonic just demoed a 3d bluray system:

http://www.blu-ray.com/news/?id=1838

Of course the person doing the review is a bit confused. Polarised
systems have always been used in theaters since the 1950s. It would be
surprising he saw presentations in anaglyphic format (red/blue or
red/cyan) outside of his house...

The good news in all of that is that if they get this to market, we
will finally see home movies in dual stream or over/under format
instead of field sequential or anaglyph.