After being inspired by a thread on the US avsforum from a bloke that modded his X1 I decided to attempt a similar mod on my BenQ PB6100! I had the machine apart for my monthly dust blob check and clean so had the ideal opportunity to attempt the mod. Using black cardboard and gaffer tape. I constructed a small diamond shaped aperture that was around 75% smaller then the lens at the rear of the projector lens assembly and attached it to the rear of the assembly lens housing. Quite simple really. Took a couple of goes to get the size right but no too difficult. I then (with trepidation) sparked up the PJ. The results. Amazing. Deep inky blacks. Much more contrast. More snap. Somehow a deeper image. It looks brilliant. It's like getting a new projector. Now even dark bits in films look right. The LOTRs cave scene were transformed. It really is incredible. Obviously there is a fair amount of lumens lost due to the diaphragm but as the BenQ is a bit of a light cannon and I project in a fully light controlled environment it's not a problem. Well worth it in terms of time and effort. Will post piccies later.