OK, I ordered a HD73 yesterday.

Trying to calculate the vertical offset, and my trig is real rusty.

92" 16:9. 45X80

Throw is 145"

Chart, that I can't make heads or tails of is on page 16 below.



http://www.optomausa.com/PDFs/usermanuals/Optoma_HD73_Manual.pdf

What i'm looking for is H sub1, which would be how far above the top of the screen the projector should hang.

So I think I need to calculate L X tan A

A being 6.52 degrees

So Tan A is .1139

So 145 X .1139 is 16.5"

Is this right?

Thanks in advance!

Using Excel, I plugged this formula into a cell: "=145*(ATAN(RADIANS(6.52)))"
and got 16.43 inches. So yes, I believe you are correct.

I am also seriously considering the HD73. I have 9' ceilings and plan to ceiling mount the projector, so I like the large offset.

- Scott

My calculations came up with 16.57 so I'd say your both on target. Might be difference in rounding in the calculators.

sconner