I want to use one of these two projectors.....
Vivitek D951HD
Vivitek H1080FD DLP
And one of these three screens.....
Elite-Screens-ER92WH1
Elite-Screens-ER100WH1
Elite-Screens-ER106WH1
How far away from the screen will the projector need to be?
Also, whats a good cheap ceiling mount for these projectors?