We have a projector in one of our classrooms which is projecting an image onto the whiteboard which is quite a bit too big (it's not a big whiteboard). However, the little lever which changes the projected image size is already pushed as far is it will go to make the image smaller. Is there any other way of making the image smaller? The people who installed the projectors into their cages (which only they can adjust by the way) didn't do a very good job and I am continually having to call them back. I'd rather not have to do so again if possible, but if there is no other solution to this, I will.
EDIT: Forgot to mention it is a BenQ PB2140 projector