HD71 Projector Brightness
Wow time. Optoma has never really created a fully tricked out "how bright can I get this projector" mode, but, I'll get back to that in a moment.
OK, starting with Cinema Mode and everything at default, the Optoma HD71 measured a whopping 1463 lumens!
Unfortunately, those default settings do not yield a great picture. After doing the usual contrast and brightness adjustments and a grayscale balance, the HD71 now measured a still incredibly impressive 1040 lumens.
I should note that Optoma has TI's Brilliant Color, and their TruVid adjustments. This creates way too many combinations, and it affects brightness tremendously.
For example, but toning down Brilliant Color from default 7, to 1, and TruVid, from default of 1, to 0, using the original settings that yielded 1463 lumens, only 885 lumens remained - a drop of about 40%.
Ok, back to the 1040 lumens. Cinema with those settings (listed in the calibration section below), looked very good.
Using those same grayscale settings, but engaging Bright, instead of Cinema, took us back up to 1635 lumens, enough to equal the Epson Home Cinema 720, but still far from the Panasonic PT-AX200U's brightest. Remember though, that even the Panasonic - at brightest, doesn't offer great color accuracy. Figure that the Optoma in bright mode, with the default settings, should break 2000 lumens, and if you really don't care about picture quality, because you are in an impossibly bright room, take Brilliant Color to 10, and crank up TruVid too. I didn't measure, but logic says the projector should get close to its claimed 2400 lumens. It won't be color accurate, but it will cut through the ambient light as well as any projector except the Panasonic, and not be too far behind it.
Let it be noted that Photo Mode measured 1290 lumens, and TV mode, 966 lumens!
HD71 Projector - Light Leakage
No real problems here. A little light out the vents, no significant impact on to the screen or front wall.
HD71 Audible Noise Levels
Tsk, Tsk! The HD71 is not overly quiet. It really is fairly typical for a DLP home theater projector. Optoma claims 27db in eco-mode, and 29 db in full power, however, I am skeptical. The eco-mode number is probably realistic, but when you go to full power (which also happens when you engage AI for better contrast), it seems like a jump of 4-6 db, and that would be, in my estimation, about right - something close to 32 - 33 db.
Those who are noise adverse will not be happy in full power or AI mode. Those who are really noise adverse, will probably look elsewhere. Keep in mind that LCD projectors as a group tend to be quieter than DLP projectors, although the HD71 is probably not really much noisier than the Epson Home Cinema 720, which is the noisiest of the LCD models.
HD71Projector Screen Recommendations
The bigger the better! Actually, the HD71 gives you the freedom to handle a large screen, like my 128" Firehawk, rather effortlessly, even in its best mode, with lamp on low.
Since the black levels are not spectacular, you may want to choose a high contrast gray surface, like the Firehawk, or more likely other more affordable HC gray surfaces, since any Firehawk, costs more than the HD71. Look to those HC gray screens from Da-lite, Elite, Carada, all of which are rather affordable.
That type of screen will work especially well if you have ambient light issues coming from side sources, as they "reject" side lighting, to a certain extent.
On the other hand, if you just want to go with a really large screen, which will spread out those lumens, and therefore produce less bright blacks, a screen like the white surface Carada, with about 1.3 gain, will let you tackle 150" diagonal screen sizes!
Still I favor going with the HC gray surfaces if possible, for the black level performance - unless you are buying primarily as a sports fan, and more interested in brilliant, vibrant action, than dark scenes in movies.