Projector Calculations [3]

The difference in pricing between the G6350NL and the G6250WNL is quite small / insignificant.

The choice of projector will depend on what aspect ratio you use most often. The G6350 is 4:3 native. This means at 1024×768, if you use a 16:10 source you will only use 640 of the vertical pixels and the rest will be wasted. The G6250 is 16:10 native. At 1280×800, if you use a 4:3 source you will use only 1066 of the horizontal pixels and the rest will be wasted. However this is a slightly higher overall resolution, 852800 vs 786432, and if you are using 16:10 then the numbers come out as 1024000 vs 614400 so there is a significant benefit there.

Currently we have the possible placement heights of the centre of the projector’s lens as being at either 2.4 metres (preferred) or 3.1 metres from the ground. The bottom of the screen will be 2.2 metres from the ground. With the screen 2.3 metres high the middle will be vertically 3.5 metres from the ground. There may be some tilt of the projector to get its image to the right height, although at 20 metres this will be small. Horizontally the projector can be straight on. It is important to allow for a reasonable zoom range with the projector distance because when the projector is tilted up or down, keystoning adjustments necessary to straighten the picture will also enlarge or shrink the picture, which then has to be rezoomed to fit.

The seating distance range implies the placement of seats should normally leave a large gap at the front, but go nearly all the way to the back of the hall.

In this particular installation, control of ambient lighting falling onto the screens is fairly critical.