I have two Powerlite S4's, both with the same problem. They are roughly 1 year old, and the problem occured a short time after replacing the lamps. It wasn't caused by the process of replacing the lamps. I have a large area in the middle of the projected image that has no blue. The shape is roughly the shape of the lens and takes up most of the image area, about one-half to two-thirds. Outside this area the picture is good, inside it is missing the color blue and has a blue outline around the perimeter of this area. It's not out of focus or distorted within the affected area. I have tried to find some info on this condition, and the only thing I come across is that on these models, the blue filter can become damaged by the lamp. This sounds like a possibility but now I need to fix it, or whatever the problem is. I am an electronics technician so this is within my capabilities, only I have no info on this fault. Any information, part numbers, or links to applicable information would be appreciated.