Rainbow Effect and ScreenDoor Effect
DLP projectors use spinning color wheels and can cause a very small percentage of people to see rainbows. It's simple, if you can't see rainbows, no problem. Of those susceptible, some are more than others, some see them almost any time a fast moving bright object moves across a dark background, or the other way around, some only notice it occasionally, and of those, many report head movements trigger it (I am slightly susceptible and agree, and add to that, also I seem more susceptable when tired). Talk about head movements, one person recently emailed me (he may have been kidding), that about the only time he sees RBE, is when munching on popcorn (and its fast moving objects...)
Screen Door Effect is caused by the fixed pixel structure creating mild distortion problems on fine textures (such as the grass on a football field), but is not really an issue with any of these projectors, since the pixels of a 1080p projector are so small. Still, the less visible the pixel structure, the less likely of ever encountering the screendoor effect. It is possible to detect it on the Epsons and the Mitsubishi, the two LCD projectors with their normally more visible pixel structures, if you sit pretty close. Still, this also should not be an issue for anyone.
On the other hand, those 3LCD projectors do have slightly visible pixel structures for those sitting very close, which you might barely notice on movie credits, large stationary white (or near white) areas, and titling in general. Epson has the newest generation of 3LCD panels, and I should note that they seem to be less visible at any distance than last year's Epsons, or the current Mitsubishi which are still using slightly older LCD panels. I doubt however, that it will be a deal breaker for anyone but those most extremely pixel adverse.
No real issue with any of these projectors, but a number of them do leak small amounts of light, that can hit the screen and around it. I do not test, and I assume that projectors with lots of lens shift, or no lens shift, but a lot of lens offset (the DLP projectors) being used, probably throw more extraneous light out the lens than those with less. With white walls by your screen, you can see light leaking from the JVC projectors and all the Optomas. The Epsons are pretty clean, as are, I think, most of the others, although I comment in each review.
Audible Noise Levels
For those really after the absolute best environment for their viewing, fan noises (and dynamic iris noise, and DLP color wheel whine), can be an issue. Almost all projectors are very quiet to effectively silent when in low lamp mode, as their fans run much quieter. It's when you use full power lamp mode that some get noisy enough to be noticed, and annoy some folks on quiet scenes, and a few are noisier still.
For this reason, for my listings below, the operative parameter, is noise while the lamp is running at full power (bright).
Excellent: Both Mitsubishi projectors, Panasonic PT-AE2000U, Sanyo PLV-Z2000
Acceptable (to almost all): Both Epson's All JVC's, Both Sony's, Both BenQ's, InFocus IN82
Worst: All Optoma's, Sharp XV-Z20000
Home Theater Projector Brightness
In last year's report, I had brightness measurements for "best" modes in the Image Quality section, and for brightest modes, here. This year, I moved everything into the Image Quality section, for better or worse. If you skipped that page, click here.
Lamp Life and Replacement
I will only note that almost all of these projectors rate lamp life around 2000 hours in full power.
Sony, and Sanyo, however, don't provide a rating for their lamp. Right or wrong, I'll assume 2000 hours in full power, that should be close. If you are worried, call them, as I tried, but they just won't quote lamp life.
Most of these projectors claim lamp life of 2500 to 3000 hours in low power mode, but not all, JVC for example says 2000 hours - either way. Mitsubishi claims a staggering 5000 hours on their projectors, in low power mode.
When it comes to replacing the lamp, many of these projectors can do it without unmounting (if you are ceiling mounted).
Those that can change the lamp without unmounting:
Both Mitsubishi projectors, the Panasonic PT-AE2000U, both BenQ projectors, all JVC projectors, Sanyo PLV-Z2000, both Sony projectors.
Those that do have to be unmounted: Epson Home (and Pro) Cinema 1080 UB, all Optomas, the InFocus IN82
Sony's VW50 has a bottom lamp door, it is slightly away from the mounting threads for a ceiling mount. Best I can say is that with the right mount, you may not have to unmount the projector to change the lamp. Consult with your dealer about the mounts.