Originally Posted by solid_dvd
I managed to get a pair of linear polarized glasses and tried it with my JVC DLA-HD1. I put the glasses on the lightpath and looked how the glasses behaved on the screen. It was exactly as in post #4 in this thread:
"If one turns black, as the other goes white, then all three colors are linear polarised at the same angle."
So if I'm hearing you right, rotating the glasses would cause the projector beam to go from full brightness to very dark with no color casts???
If that's the case, it means your projectors are linearly polarized and ok for passive 3D per the recommendations radjam has been describing. Both linear and circular polarization are "passive". They're just two different ways of handling the polarization (different projector filters and different passive glasses).
Your best solution since both projectors are polarized at the same angle, is to get two retarders and place them in front of your projectors to achieve circular polarization. Depending on the rotation of the retarders, you will get CW or CCW polarization (CW for one projector and CCW for the other). To rotate the linear
polarization of your projectors to 45 and 135 degrees, you would use a linear polarizer in front (screen side) of the retarders, which loses more light. For this reason, staying with circular (just the retarders) is best. Also, with circular, you can use RealD glasses which are readily available.
The retarder material is available from polarization.com (http://www.polarization.com/polarsho...0e11b8b936e639
They sell it by the foot in 36 inch width for $35US/foot. I don't know if they do international shipping, but they most likely can, if you request it.
Rdjam was going to do testing on some screen fabrics but I haven't seen his posts yet, so you might address that question to him. I do know Harkness has a new material out for passive 3D which is somewhat better than their Spectrol240 (It's called "Stagelite", I believe).