[MF3D.FORUM:1004] Projection Lenses

[Tom Hubin <thubin@xxxxxxxxx>]

Hello,

35mm projectors typically offer 3 focal lengths for projection from the
front, middle, and back rows of the audience. Is this also true for MF
projection?

What focal lengths and fNumbers are used for various projectors?

What does a new or used, mono or stereo, MF projector cost?

Is an MF projector generally larger and/or heavier than a similar 35mm
projector?

I have been doing some number crunching for condenser optics for various
theoretical slide formats and projection lenses. My math indicates that
for a well designed illumination system (light source plus condenser
optics) that the lower the fNumber of the projection lens and the larger
the slide format, the more light delivered to the screen. Any comments?

I do not mean to suggest that you can increase the diameter of your
projection lens to get a brighter screen image. But rather that the
illumination source and optics are designed to fully fill the projection
lens that is intended for use with the projector.

So is it generally true or untrue that MF screen images are brighter
than 35mm screen images?

Is this too technical for this list? Should I move the questions to
Tech3D? I lapsed from P3d and T3d when they went to a new server. I was
very busy at the time so I just let myself fall off the list.

Tom Hubin
thubin@xxxxxxxxx