Need advice for projector and screen solution

[e.pel...@gmail.com]

Hello,

we are planning several shows were big projection screen would be used as a background, but I am new to these solutions, so I need some advice.

Requirements for screen:
size - ~7m x ~4x (~22ft x ~13ft)
rear projection
view angle - >120° (because people will be as near as 6m)
screen need to be compatible to projector with ultra short throw lens (as I understood not all can do that?)
screen need to be portable


Requirements for projector:
need to be compatible with ultra short throw lens (space in the back is limited - 4-5m)

and with projector there is a lot of other questions:
which technology is better - DLP (issue - rainbow effect) or LCD (issue - screen door effect, dead pixels)?
how many lumens I need for big screen with no other light/small lights on scene for clear background?
why projectors contrast vary from 1000:1 to 1000000+:1? Or is it no big deal?
which projector light technology is better? Is it worth to change metal-halide lamps or is it better to use laser technology?


I found only scraps of information about big rear projection screen so I would appreciate any information about that.

Also I found projectors variety in technologies used for lighting, image forming and other parameters combinations overwhelming for new guy so I would really appreciate if You could share Your knowledge and experience.

[kd5...@endofnet.com]

You can use mirrors to increase the "distance" of the throw.

[e.pel...@gmail.com]

On Friday, June 2, 2017 at 3:44:23 PM UTC+3, kd5...@endofnet.com wrote:
> You can use mirrors to increase the "distance" of the throw.

I need this for mobile show, which will be assembled and disassembled every time so mirror set up would just add additional work.