P3D Re: Stereo Projectors

[fj834@xxxxxxxxxxxxxxxxxxxxx (Dr. George A. Themelis)]

> - but my photo dealer told me that only with the most expensive brands
> it would be garanteed that both lenses have exactly 90mm. Otherwise it
> would be impossible for the brain to make one 3D picture out of the two
> pictures.

To put it mildly, your photo dealer is exaggerating a bit.  Instead
of fixed focal length, try zoom lenses in the projector.  You can match
them at any focal length (within their range) you like!  But most people
would be happy with two random fixed lenses.

> Also he showed me a special silver screen without any surface protection
> and said that other screens would depolarize some of the light.
> This special screen was about $150 per m^2 and every contact with it
> destroyed parts of the surface. Not very nice...

Again, he might be exaggerating a bit.  "Silver screens" in the USA are
very inexpensive, from $1/m2 (in flea markets) to around $150 for my
new 70" screen brand new from B&H.

George Themelis


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