Check out this post in the official Benq w7000 thread in the 3k+ forum:How the Benq IRIS works
We documented how the IRIS works so you can lower the brightness properly if need be. The brightness and contrast controls should NOT be used to counter the projector being too bright. These controls are instead set with a Pluge Pattern (you can get a free Pluge from the AVS Rec709 Test Disk in this forum (Click here for instructions on how to burn the Rec 709 test disk to use in your Bluray Player - This Thread
. If you do not feel like doing this at the moment, just leave them at 50/50 default settings, but don't adjust brightness and contrast just to attempt to darken the image.
The brightness control does not negate all brightness on the black floor, it is just lowering the black floor to a given point of crush, but it can only lower it so far. This is a very bright projector, and the ONLY proper option is to use the IRIS in the service menu to tone down the brightness. In the service menu, you can also control how aggressive the IRIS reacts to dark scenes by changing the MIN IRIS position while leaving Dynamic Black enabled. You can make the screen pitch black if you want, but I wouldn't recommend it necessarily as it would make the IRIS a bit bouncy.
On a new lamp, most smaller screens should be TOO LIT UP, and have too much light on it and look grayish (this is normal), but this totally depends on how bright you have it and how big of a screen you are using. The beauty of the Benq is that it has an IRIS setting we can fix this with. To adjust the IRIS in the service menu, go to the Information Menu, then press UP-Down-Up-Down-Up-Down and then the Enter button. Now be careful in the SERVICE MENU as you don't want to change something that might screw with the PJ. Go to the second menu from the right, you can change Current and Min Aperture Position to darken the overall image, but this will disable the Dynamic IRIS. If you leave Dynamic Black on and just lower Min Aperture setting, then it will make the dynamic IRIS more aggressive, but if you turn off Dynamic Black and lower the Min. Aperture position, then it will force the whites and blacks to stay darker (so the second option lowers complete light output, but the first option - leaving DB enabled only lowers the black floor in the method of how DARK the IRIS can go in dark scenes, rather than lowering white peaks).As far as light leakage:
Hmm, look for sources of light leakage in the PJ itself, possibly coming out the side vents?
I didn't notice any light spill from my Benq, but I did not look carefully and as I have a black ceiling it would be harder to tell.