Originally Posted by Seegs108
What about the projector? It needs to be perpendicular to the screen (perfectly) and it also needs to be level (perfectly) if you want it to line up right. If by your judgement it looks perfect, or about as perfect as you can get and you're still having issues you may want to contact Sony. Maybe something is off with the projector itself.
Don't use the keystone. In the end it affects picture quality and 99% of the time isn't necessary. As posted above the screen needs to be level across the width and more importantly plumb top to bottom and screen material should hang flat. If that is done, you should be able to square up the image by using adjustments on the projector mount coupled with the lens offset controls. I took the liberty of posting a cut and paste of a post by Mark Haflich in the HW30 thread regarding alignment of a projector. I think it explains the process well:
" No professional mounter would EVER use a level on the projector. You hang the screen and put a level on top of the frame to make sure it is horizontally level. That's it. Put the level away.
You tilt the projector up or down to make the top and bottom of the rectangle the same length. You bank the projector left or right to make the top edge parallel to the frame. You zoom the picture in a bit to se the projected edges a little inside of the frame and then zoom out later. If the side edges are tiltedyou need to rotate the projector so they are no longer tilted. As stated above, you are making the lens pasrallel horizontally by this rotation. both sides of the lens will now be the same distance from the screen. Titlting the projector up down does the same for the top and bottom of the lens. Obviously to center the whole rectangle you will probably need to use some lens shift vertically. try not to mount the projector any higher than lens center at top of viewing screen height. Try not to use horizontal lens shift y mounting the lens center in the horizontal screen center. If you don't understand all this, please give me a call tomorrow morning.
The reason no levels are used is that your wall is probably not exactly level vertically or even square to the side walls. You are adjusting the projector orientation to msake the lens exactly parallel to the plane of the screen. "