Why is the unsupported (I guess this could be taken two ways but I'm referring to the type of material stretched over a frame) matte white 1.0 gain not mentioned on their web site? I am about to buy two screens (4:3 90" diagonal) so I called Stewart for a sample of the 1.3 Studiotek and offhandedly asked why they didn't have a gain 1.0 unsupported material. Super nice guy Andrew told me they did and said he would enclose a sample of it also.
My interest in the 1.0 stems from the following experience. A few years ago I had a sample of the 1.3 to play with. I was projecting (CRT) on a white wall at the time. I taped the sample in the middle of the projected image and the sample rectangle *was* slightly brighter than the surrounding white wall. I then moved the sample horizontally to one of the edges of the screen and the rectangle was noticeably darker than the wall. We were essentially robbing Peter to pay Paul. Observations were made from the center of the screen standing behind the floor-mounted projector.
CRT projectors are already about twice as bright at the center of the image than at the edges right? Then why would we want to compound this effect? It seems the only answer might be that the majority of the time one is looking at the center of the screen and this will appear brighter. But how about the off-axis viewers whose brighter area will tend toward the left side of the screen if they are sitting left and vice versa if they are right of the projector.
Of course the physics of this phenomenon all make sense. The angle of incidence equals the angle of reflectance with a mirror. And we are ever so slightly approaching a mirror.
This is why I am tending toward the 1.0 material. I will repeat this my test upon arrival of the samples and report.
Please tell me where I am wrong or agree with me. And has anybody had experience with the Stewart 1.0 material? Reflecting qualities aside does anybody (including Stewart) claim that the 1.3 is spectrally superior to the 1.0?
[This message has been edited by Robin (edited 01-08-2001).]