Projection

Samsung SP-P300 projector

I spent some time today playing around with projection onto the screen. At the moment I'm using a Samsung SP-P300 projector (shown above) which is amazingly small but the projection isn't very bright (only 24 lumens) and the throw distance (distance required between projector and screen) to get a good sized image is fairly large.

Ideally I want to place the projector inside the bookcase as this will prevent occlusion problems when people use the screen and also the HoloScreen apparently works better when the image is projected from the rear. However, due to the throw distance of the projector putting it inside the bookcase doesn't give an image which fills the entire screen.

With the lights on the image isn't particularly bright and doesn't fill the entire screen

With the lights out the image is much brighter

For now I decided to project from the front of the screen using a throw of around a metre. This fills the screen although the image isn't very bright and also projects onto the back of the bookcase. I also used NVKeystone to adjust the keystone effect caused by the projector being at a 30 degree angle to the screen. Having this feature is really handy, particularly for projectors like the SP-P300 which don't let you do proper keystone adjustment. Pictures comparing front projection with and without keystoning are shown below;

Front projection without (left) and with (right) keystoning

I'm still thinking rear-projection is the way forward so I either need to find a standard projector with a shorter throw, or use something like the NEC WT-610 which only needs a 6.4cm throw distance for a 40" screen (I've spied one of these being used in the Department but they are really expensive), or the alternative is to use some kind of mirror arrangement at the back of the bookcase to get the required image size.