i need to mount my RS2 inverted on a shelf in the rear of the room, is there any suggestions on how i can mount it? i will need some kind of support on the RS2's top to hold it away from the shelf so it will sat level and fall down. does someone make a item for it to sit in? thanks

I guess the obvious question is why do you need to have it inverted when sitting on a shelf, instead of right side up on its own feet?

i have to mount it up high because of the bay window it will sit in front of and i want it out of the way above the window. thanks for the reply.

The lens shift works symmertrically - it's +/- 80% from lens centerline vertically, so if you don't have enough lens shift to make it work sitting on the shelf, you won't be able to make it work inverted either. I think that's why mike asked why you wouldn't just set it upright on its own feet.

Now I understand the original question. Yes as HogPilot said the lens shift is the same both plus and minus, so it does not matter if the projector is right side up or upside down.

If you have the shelf centered, so you do not need any horizontal shift you should be able to have the projector lens 80% of the screen height above the screen.