What about throw distance?

The throw distance of your set-up is the distance from the front of the projector lens to the screen. In home cinema systems this is often dictated by where you can put the projector from which you can work out the throw ratio you will need. Say you have decided that you want a 2 metre wide image and you'll be putting your projector on a shelf at the back of the room 4 metres away from the screen. This gives you throw ratio of 2:1 (the distance to size ratio).

To find a list of projectors which will produce a given image size from a given throw distance try our Throw Finder.

If you know the image size and the projector you want then use our Throw Calculator.