I would like to know how to calculate the correct vertical offset with Elite Screens 120" diagonal with 24" inch black top? Screen with 96" and height 72" now lets add th 24" black top to that overall height we get 72"+24"=96" total height.
Projector is BenQ W1070. On their website specs they say it has:
Projection Offset- Vertical 110%-130% +-5%
Here is the artcle which explains how to calculate vertical offset with those previous numbers (total screen height & projector offset).
The correct height from ceiling is calculated like this, taking into account the projector offset by manufactures specs.
Example from the article.
"JVC models offer 80% offset but above and below the screen whereas some models offer different and lesser amounts for up and down.
Here’s how we can make practical use of offset with our JVC projector. Start by multiplying the vertical height of the screen – 56-inches – by 80% which results in 44.8. Then take one-half of the screen height – 56 * .5 – and you get 28. Now subtract 28 from 44.8 and you get 16.8. This is the amount that the center of the lens can be above or below the screen."
If I use these calculations with BenQ's 110% offset, I get ridiculous offset! Basically I have to mount projector 57" from the ceiling. I have 118" long walls so the projector will dangle half way down?!
Or am I calculating something wrong?
Help needed, this is my first HT project ever.