Mounting the Projector
The HD72 has a 6.50 offset from the center of the lens to the
closest edge of the image. For instance, if the projector is 10' back and
everything is level, the edge of the image will be 13.7" below the center of
the lens for ceiling mount, or 13.7" above the center of the lens for table
For a 100" wide 16:9 (1280x720) or 5:3 (1280x768) image, the HD72 can
be anywhere from about 158" (13' 2") to about 190" (15' 8") back. With the
offset, as well as the throw range, it is important to determine whether this
projector will fit well into a room. The offset may help in rooms with
extra tall ceilings, but it would be a little difficult to deal with in rooms with
short ceilings. Tilting both the screen and the projector can help
counteract this fixed offset in setups where it does not work naturally, but
this is really only for those willing to consider a little bit more
difficult install than normal.
This projector has a feature to shift a 1280x720 image within the 1280x768
space vertically. Those choosing to use this projector with a 16:9 screen
will end up with light spill above or below that area that is as bright as
the black level of the projector. Masking or having this area behind the
screen will pretty much make this invisible. A 15:9 (or
5:3) screen should match the image shape well, but would mean black bars with most
content without stretching.
While a minor issue, I noticed some light coming out of the bottom of the
projector (upper part when ceiling mounted) while in use. With the bottom
facing a bright surface this could allow some extra reflection into the
The lens had more chromatic aberration than I expected. Zooming the lens causes the image to
go out of focus, so both have to be adjusted together.
As can be seen in the photo below, as far as digital inputs, the HD72 has both an HDMI input
and a DVI input. Having two digital inputs is uncommon even in projectors
costing much more than this one. There are fairly inexpensive adapters that
can be plugged into either input so that DVI cables can be connected to the
HDMI input and HDMI cables can be connected to the DVI input if desired.
However with one of each digital input type, the projector is ready to go for
either DVI or HDMI cables without picking up an adapter.
I found that the DVI input behaved like a
standard HDMI input, so it seemed to be DVI in only a physical connector way,
other than also accepting DVI-A (or analog signals). What this means is, for
source devices which have problems with their levels, colors, etc., when
connected to DVI inputs, this does not apply to the DVI input for the HD72.
For instance, as of the writing of this article, the Toshiba HD-A1 HD-DVD
player crushes below-black levels or expands video levels to PC levels to
standard DVI inputs, but does not have this problem when connected to the
HD72's DVI input, because the HD-A1 doesn't crush below-black levels to
standard HDMI inputs and this is basically what the HD-A1 detects over the
I found that changes to settings in the menus, while using the DVI input for
digital signals, stayed when switching to the HDMI input and vise versa.
Without separate settings for the two inputs, it would be difficult to have
separate calibrations for them, such as if one were to be used for standard
video sources with standard video levels, and one were to be used for source
devices sending out standard PC levels (like a PC).
The physical DVI input can also be used for analog signals from a PC by
using a VGA to DVI-A cable or similar, but I did not try this.
Here is what I measured for Color Temperature, RGB Levels, and Luminance
(Gamma), respectively, with default settings in Cinema mode.
I then calibrated the projector, and here is what I measured for Color
Temperature, RGB Levels, and Luminance (Gamma), respectively:
As shown by the RGB levels, there was some red drop-off near the highest IREs,
which could be seen with a gray ramp as a little more reddish hue at 90 IRE
than at 100 IRE. I did not see an easy way to fix it and left it like this.
At this point, there were about 30 hours on the lamp, which was set to low, and I used my
settings I had decided on for Cinema mode. Using the 16:9 portion, since
this is what I expect most people using this for home theater to use, I
measured about 290 lumens and 1100:1 On/Off CR. Raising the Contrast and
the value for Brilliant Color, while leaving the lamp on Low (without worrying about color
balance), would have given about 700 lumens and 2750:1 On/Off CR. For ANSI CR
I measured about 540:1, which is very good and in the normal range for DLP
projectors (which tend to be higher than other projector technologies).
With the HD72, High Lamp to Low Lamp has a ratio of about 4/3. In other
words, High Lamp is about 33% brighter than Low Lamp.
I used the Toshiba HD-A1 with HDMI for playing HD DVD content, clips of various HD content I had burned
onto DVDs, and commercial DVDs.
I did most of my viewing with the HD72 from about 1.5x the screen width,
which I feel would be a reasonable viewing ratio for most people.
With a test pattern of a smooth grayscale, the HD72 did pretty well at not
adding false contouring or banding. With some short clips I use for
testing, it did well in avoiding false contouring with some, but not all.
I normally do not see many color separation artifacts (rainbows) with single
chip DLPs having 5x color wheels. With the HD72's 4x color wheel that has a white
segment, I saw more rainbows than I am used to at first, but they decreased with some
viewing. Given that my experience is that the vast majority of people who
don't know about the rainbow effect don't report seeing any problems similar
to these when asked with DLPs with 3x color wheels, I wouldn't expect most
people to see these artifacts with the HD72. However, those prone to seeing
these with other home theater DLPs would be likely to see them with the
The shadow detail was about in the range I expect from single chip DLPs with
no dark segment(s) on the color wheel, meaning that it was pretty good, but
not as good as single chip DLPs with dark segments on the color wheel
generally perform with some material.
The HD72 provides crispness to many of the images, which I find with DLPs in
general. These can also look more detailed than some alternative projector
types, although with low quality sources this can mean more visible
artifacts also. With high quality HD DVD sources, the image quality looked
outstanding from my viewing position.
The Optoma HD72 is priced within a very competitive section of the market.
Optoma has its own HD70, and Mitsubishi has the HD1000U below the HD72
pricing. There is also the Panasonic TX100U LCD at around the same price as
For those who can deal with the throw and offset
limitations of the HD72, it looks to be a competitive unit. With a higher
budget, I would personally look for a 1280x720 DLP without a white segment
on the color wheel (including Optoma's own HD7100, among others) if sticking
with DLPs, but there are those who will value the white segment and brighter
environments where that segment can be useful.
- Darin Perrigo -