[photo-3d] Silver screens

["John Goodman" <jgood@xxxxxxxx>]

Using aluminum powder metallic paint to make inexpensive 
stereo projection screens seems like a miracle, as any smooth 
surface can become a window to projected 3-d images. But 
achieving the best results (as always) seems to be an art.

My first aluminum paint screen had a one-coat thick sprayed 
surface, and the results were satisfactory, if not outstanding. 
The next iteration has an additional sprayed coat, textured with 
a half-dry paint roller to stipple the surface, hopefully to provide 
a brighter screen with less directional reflectivity. It seems to be 
a slight improvement over the sprayed-only version, but there 
is still considerable directionality. There's a relatively narrow 
brighter area along the reflected axis of projection, with a 
corresponding falloff in brightness elsewhere.       

I'd be grateful for practical input from people who have 
experience with both DIY aluminum paint screens and the best 
commercial silver screens (such as Stewart Film's Silver 400 ?). 
Do all silver screens by their nature suffer from pronounced 
brightness falloff at relatively narrow angles of incidence? How 
pronounced is this for the best commercial examples? For 
small screen sizes (say 4' x 6' or smaller) the perceivable detail 
in slides seems to be finer than the pitch of some lenticular 
screens, so the "grainlessness" of silver screens is very 
attractive.       

John Goodman