Help finding a members Theatre Room post

This one isn't curved, but there are some good ideas:

http://www.hometheaterforum.com/forum/thread/235970/diy-screen-vs-professional-screen-projector-central-article

Leo seems to find most screen threads, so I'll ask him to add his $.02 he might remember it. 

Off hand, do you remember the "direction" of the curve?  As in, was the screen intentionally being "bent" so as to replicate the old Cinerama-style screen?  Or was it just that, for whatever reason, the tubing edges were bent?

I know I have talked about my obsolete screen where some of the pipe edges were iron, and some were PVC (and thus flexible,) and intentionally not rigidly attached so I could re-tension the screen as the material stretched..

Leo

I don't think this the one you are looking for, but FYI -

http://www.hometheaterforum.com/wiki/how-to-build-a-diy-black-out-cloth-screen

Well, I have to admit not recalling seeing this thread.  However, some practicalities:

It's not too hard to make a rig for bending pipe.  Getting the two pieces of bent pipe to be perfectly parallel, however, would probably be something of a trick.

(at my college theater, the TD built a rig for bending, with a gentle curve, Schedule 40, 1.5" black iron pipe.  The contraption was pretty simple, with two fixed rollers, and a third roller between them on a vice-like apparatus.)

That was, of course, for a simple curve.  If you want to make a compound curve (as in, a spherical, or semi-spherical section,) then it's either much easier or much harder.  My recollection is one of the cinema chains did this in some of their "high end" screens.  The screen was a solid surface -- a mylar or something like that -- that was put into a sealed box frame.  The air was pumped out of the box, sucking the screen "into" the box forming a perfect -- or near perfect -- multi-axis curve.

Their bigger complication was they could no longer put speakers behind the screen, and ended up putting smaller, "thinner" speakers along the top and bottom edges of the screen.

I can't remember the advantage that the cinema was expecting to get; I don't recall them having any east-coast cinemas.  (Or maybe they did.  High Performance... something something something?  Bother.  Probably about 12-15 years ago now that I saw the article.)

Leo