What to look for in a high definition
projector
High definition projector aspect
ratio
This is really a no brainer. Make sure that
your high definition projector has a 16:9
aspect ratio (as opposed to a 4:3 aspect
ratio). High definition projectors designed as
home theater projectors will be designed to
handle high definition so they will be 16:9 or
widescreen format. The traditional 4:3 size
aspect ratio is still a common choice for
business projectors, but not home theater
projectors.
High definition projector resolution
This one is a bit more controversial, at
least for the time being. There are two choices
- 720p or 1080p native resolution. Both of
these resolutions are considered high
definition. Until recently 720p was pretty much
the standard choice for a high definition
projector. As 1080p is quickly becoming the
standard resolution of most new flat panel tvs,
it has also affected the projector market as
well.
Prices have rapidly decreased to the point
where a 1080p projector is a serious option for
shoppers. So why the debate? Isn't the higher
resolution automatically better? Yes and no.
All other things being equal, yes 1080 lines of
resolution is theoretically better then just
720, just as 720 was better then 480.
On the other hand the location of the viewer
to the screen is important to know. A general
rule of thumb is that the average eye of the
typical viewer will not notice much of a
difference between 720p and 1080p if they are
sitting 1.5 times the screen width or greater
away from the screen. As you move closer to the
screen you will tend to start noticing the
pixel structure and this is when you can really
benefit from 1080p.
The other thing is that there just is not
much 1080p content available. Blu-ray is in
1080p and if you currently have a Blu-ray
player or intend to get one in the near future
you will want to seriously consider going with
a 1080p projector to get the most out of your
player. High definition television is currently
being broadcast in 720p or 1080i so you do not
need 1080p to view this content in it's
intended resolution.
There is no doubt about it. 1080p is here to
stay and a year from now the debate will
probably be a moot point as most projectors
will probably be 1080p, but for now you need to
decide if it is worth the premium cost to have
a minimal improvement for your system. If you
suspect you will have buyers remorse you can
save yourself the anguish and get a 1080p now
for peace of mind. On the other hand as prices
continue to fall you could get a great deal on
a 720p now and upgrade in a few years for the
same cost as buying a 1080p now.
Native resolution is one of the more
overrated considerations when buying a
projector. A high quality 720p projector is
certainly going to outperform a low quality
1080p projector. There are many other important
considerations such as picture sharpness,
brightness and contrast levels.
Brightness
The home theater projector's brightness
level, measured in ANSI lumens, is another very
important consideration. This becomes more
important depending on your viewing
environment. If your room has a lot of ambient
light (through windows for example) then it is
essential to have a bright projector. If you
intend to use your projector strictly for
movies in a room with no light then it may not
be your primary deciding factor.
I once was told that lumen rating is the
best way to tell the quality of the picture
that you will get. That simply is not
necessarily the case. A home theater
projector's goal is to produce the most
lifelike picture possible with vibrant colors,
sharp detail and deep black levels. Projectors
designed for business presentations need higher
lumens/brightness level because it is needed to
make presentations in areas with ambient light,
however if you took that projector home and
tried to watch a football game in high
definition on a 10 foot screen with that same
projector it would look horrible, trust me I
know from experience.
As a general rule of thumb 1000 lumens
should be sufficient for a dedicated home
theater with complete light control. A room
with high ambient light on the other hand will
want 2000 or more lumens in order to project an
image adequately, where a room with some
ambient light will want 1400 or so lumens.
Contrast ratios
Another important consideration is the
contrast ratio which is the difference in
brightness between the deepest black and
whitest white. A higher number means a higher
contrast.
Contrast is what gives your image a lifelike
quality. A projector with high contrast can
produce deep blacks with good shadow definition
whereas a projector with lower contrast will
appear more gray and washed out and will lack
the depth that is needed in order to produce
stunning images.
So what contrast levels do you need? This is
a bit of a tough question. There is no black
and white answer to the question as contrast
ratios are measured slightly differently from
company to company, but again as a general rule
of thumb 2000:1 is a good starting point for
entry level projectors. A 5000:1 ratio will
give better blacks and shadow details and is
common in a midrange projector. A 10000:1
contrast ratios and above are obviously better
yet and are capable of producing deep,
lifelike, almost 3d images.
One thing that you will come across if you
study the contrast ratios of different
projectors is a dynamic iris. A dynamic iris is
built into many projectors to improve the
contrast by automatically opening the iris in
order to achieve the whitest whites and closing
it to achieve the darkest blacks. Keep in mind
that a projector with a dynamic iris will
generally measure their contrast based on the
whitest whites and deepest darks based on the
variations of the iris so this can tend to make
the contrast ratios misleading on some
models.
NEXT
What to look for in a high definition projector
(part 2)
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