Geez, I just wrote a page on how to setup a projector and it didn't post... Don't you hate when that happens?
http://www.projectorcentral.com/pdf/projector_manual_5039.pdf
This projector has no lens shift and the poster that said that it did is likely referring to page 28 of the manual which lists some digital masking and shifting features which is not at all what lens shift is. Lens shift is the physical shifting of the lens itself to move the image up and down on the wall itself so it hits the screen properly.
Digital correction is the process by which pixels are turned off, and actual resolution is dropped, and processing is added which hurts image quality, but allows for some change when a projector is not positioned where it should be.
The OP has some idea of the right way of doing things, but sounds like he must have made a few significant errors.
1. You've gone to projector central, as listed above, and you have a throw distance of 10' to 12' with an offset of 7.2".
2. This means the LENS TO SCREEN distance must be between 10' and 12' - that's the front of the lens to the screen, not from the projector case to the screen. Doesn't matter in that 2' range where the lens is, just make sure it is in that distance.
3. If the top of your screen is 17" away from ceiling (AFC) then the CENTER of the projector lens must be 7.2" above that, or 9.8" AFC.
4. The projector mount you use should allow the projector to be properly lowered so that it is 9.8" AFC. Using a mount like this one allows the use of standard 1.5" pipe, available from Home Depot or Lowes (pluming section)...
http://www.mountdirect.com/Projector_Ceiling_Mount_NPL_Series_p/npl.htm
Under $50!
5. There is no reason the projector would ever project onto the ceiling if you have it mounted near the ceiling unless you have it on a shelf instead of UPSIDE DOWN ON A MOUNT. I say that loudly, because if you say it's on the ceiling, then I say you have your projector right side up instead of upside down. That, or you are pointing it upward.
Follow up with us, let us know, but it sounds like you have it on a shelf or something at the back of the room, and you need to flip that projector over, using a mount like the one I linked to, and get it in the correct position.
Make sure the LENS is on the center of the screen when mounting. This will mean shifting the projector a bit to the left to make the lens on center (when upside down).
If you are off by an inch or so it won't matter. Typical overscan is 3% to 5%, 1" off at 144" throw distance is well under 1%, so the amount you are off will fall into the black area of your projection frame. This is why you always want a good black border around a screen.
Follow up if you have any questions! (copy entire thing, then press 'POST')
