I recently purchased the SP4805 along with the 106" Draper Screen. I have not yet ceiling mounted the projector. It's currently sitting on top of my equipment rack, about 18' from the screen. The colors and detail in the picture are outstanding. The only problem I'm running into is what I would call a kind of strobbing effect. It doesn't happen in all movies, but it's very noticeable to me in some. For example, when I play Pulp Fiction, there are certain colors in the picture that you can see sort of rolling patter going up from the bottom, and it can be quite distracting at times. And with the movie Troy, any time there is a scene with bright sunlight, you can see a sort of flicker in the brightness. For example, when Achilles is ridding up on his chariot to fight Hector, and the camera is panning over the walls, the portions in direct sunlight look as though someone were randomly flicking a switch causing the brightness to flicker between light and slightly darker. The effect is also noticeable on the sand. Is this a problem others have run into? If yes, how did you solve it? If no, does any one have a clue what could be causing it? Could I possibly have a defective unit? Any answers would be GREATLY appreciated. Thanks.