How far from the wall?

[icideal]

How do I calculate how far from the wall to place my projector if I want to end up with an image that is 8' wide.

[karm100fists]

I THINK you just look at the throw ratio and cross multiply

for instance if its 1.75'~2.8'

then

1.75/2.8=x/8

That's my understanding anyways.

[BMXTRIX]

The best way is to look (download) the owners manual and look at the exact throw ratios for the particular projector you own. I have never been 100% sure how the ratios are dictated in specs. It should be a range since most newer projectors have zoom lenses. So, you get a 1.2->1.8 zoom lens on a 16:9 projector and (I am NOT sure about this part) you take your screen width and muliply it out. It would be between 1.2*8 and 1.8*8 feet away from the screen. Which is about 9.5 to 14.5 feet.

This may be a little wrong, but I think it is close... or I could be totally wrong. I would like to nail down what the ratio is supposed to be when it is specified in a manual or on www.projectorcentral.com - There is a pretty good distance calculator on that site.