Effect of Zoom Lens Position on Brightness
As the VPL-PHZ10's zoom lens is only a 1.45:1 there isn't a huge difference in brightness depending on the lens position.
To look at one mode, Presentation, zoomed to:
Full wide angle (closest): 4781 lumens
Mid zoom: 4641 lumens
Telephoto: 3704 lumens
All considered, the drop from closest to furthest placement is just over 20%. The drop from wide angle to mid - less than 5% (barely visually detectable).
Bottom line: Loss of brightness by mounting the projector further back is not significant enough to be a consideration. In other words - mount this projector (distance wise) wherever it works out best based on the room design and placement.
No complaints here. The projector provided good sharpness across the range from center to corner, with only slight softness if the focus is made on the dead center of the image.
The images above consist of two pair where we show full screen, and then a zoomed in look to see how sharp the text and graphics are. The last two images are of an image gallery with lots of small type, and a typical text only pdf document of the type that might typically be found in collaboration meetings.
Small type down to 8 points is readable (but 8 point is definitely marginal). The good news: No one normally uses 8 point type especially when projecting at 1080p. (Note, 8 point type on a 1080p projection is smaller than 8 point type on 720p projection.) Spreadsheets and Word type documents are typically 11 or 12 points, Powerpoint body text is usually 24 to 36 points and rarely ever less than 18 points.
Bottom Line - VPL-PHZ10 produces a nicely sharp image for a 1080p resolution projector. This is a 3 panel device, so there's some mis-convergence to be expected. Considering this is an early engineering sample, that mis-convergence was pretty minimal, more typical of what would be expected in full production. The Sony has a digital convergence feature to further minimize the perceived mis-convergence. I did not test it (since this was an engineering sample), but we have found Sony's implementation to be effective on other business, as well as high end home theater projectors. (The no mis-convergence at all of single chip DLP projectors is still more precise of course, but, the difference is going to be a non-issue in a presentation/collaboration environment.
Recommendation: When setting the focus, pick a spot between 1/3 and 1/4 of the way from the center to the corner. That will still provide really sharp focus in the center of the screen, and have the corners looking slightly sharper than if you focused on the center.
I haven't seen a decibel spec for these affordable laser projectors, but for a 5000 lumen projector the Sony running at full power, is going to be a little quieter than most. If I had to guess, I'd estimate the Sony (based on what other projectors claim) to be no more than the mid-30 db range. Considering the louder home theater projectors get up into the low 30 db range, that's pretty good. There are plenty of 5000 - 8000 lumen projectors in the 39+ db range. Count the VPL-PHZ10 projector, therefore, as being quieter the most of the similarly bright competition.