CHOOSING A GOOD PROJECTOR
Portable :
Sizes range from small and light enough to fit in a shirt
pocket to suitable for permanent installation only. Most projectors fall in the
middle: light enough to carry, but not necessarily light enough to go with you
on every business trip. You may not mind carrying a 2- or 3-pound projector at
all times, but you may consider a 10-pound projector worth taking with you for
special occasions only.
What Resolution Do You Need?
Ideally, you should match the projector's native resolution
(the number of physical pixels in the projector's display) to the resolution
you use most often. Projectors can scale images up or down to their native
resolutions, but they sacrifice image quality in the process. You should also
consider the kind of information you'll be projecting. For a typical PowerPoint
presentation, SVGA (800-by-600) will save money compared with getting a higher
resolution. If the presentations will include things like spreadsheets,
consider XGA (1,024-by-768) to show more detail at a time and still ensure that
it's readable. For still more detailed images, like engineering drawings,
you'll want even higher resolutions.
Do You Need a Widescreen Format?
Projectors with native widescreen resolutions are becoming
more common. If you create your presentations on a widescreen notebook or
monitor, they may look better if you project them in a widescreen format as
well. Be aware that widescreen resolutions vary, however, so make sure you
check that the actual pixel count of your computer and the projector resolution
are a match. WXGA, for example, could be 1,280-by-720 or 1,366-by-768.
How Bright Should It Be?
There is no one best level for brightness, and brighter
isn't always better. The best level depends on the amount of ambient light, the
size of the image, and even the screen you're using. As a rule of thumb, for a
portable projector to use in well-lit locations, 2,000 to 3,000 lumens is the
right range. If you're setting up the projector in your own office, however,
keep in mind that too bright an image is hard on the eyes. Buy from a knowledgeable
source that can help you match brightness to the lighting conditions and screen
in the room.
Keep in mind, too, that small percentage differences in
lumens—2,000 versus 2,200 for example—aren't terribly significant. Perception
of brightness is nonlinear in nature, which means you need far more than twice
as many lumens to appear twice as bright.
Don't Take Contrast Ratio Too Seriously
Contrast ratio is the ratio in brightness between the
brightest and darkest areas a projector can produce. All other things being
equal, a higher contrast ratio indicates more vibrant, eye-catching colors and
more detail showing in dark areas on the screen. Because other factors are also
involved, however, knowing the contrast ratio doesn't really tell you much.
How Do You Plan to Connect?
Most projectors offer at a minimum an SVGA (analog)
connector for a computer and a composite video connector for TV signals. If
your computer has a digital output (typically a DVI or HDMI connector) you
might want a digital connection on the projector as well, since it will
eliminate any chance of problems like jittering pixels caused by poor signal
synchronization. Most projectors today, however, offer rock-solid images even
with analog connections. Keep in mind, too, that many notebook computers don't
offer a digital output, so you may need to use an analog connection even if the
projector has a digital connector.
What Technology Do You Want?
Today's projectors are based on one of three technologies:
DLP, LCD, and LCoS. Most DLP business projectors project their primary colors
sequentially rather than all at once. This leads to a rainbow effect, with
light areas on screen breaking up into little rainbows for some people when
they shift their gaze or something moves on screen. Those who are sensitive to
this effect can find it annoying. LCD projectors don't have this problem, but
tend to be bigger and heavier than their DLP equivalents. The general consensus
is that LCoS projectors offer the best quality images, but they tend to be even
bigger and heavier than LCD projectors, and far more expensive than either of
the other two types.
Do You Need Audio?
Not all projectors include audio, and in those that do it's
sometimes all but useless—particularly with highly portable projectors. If you
use sound in your presentations, make sure that the audio is both high enough
quality and loud enough to meet your needs. Alternatively, consider using a
separate sound system.
Do You Need a Big Image in a Small Room?
Finally, consider whether you need a short throw—meaning the
ability to cast (aka throw) a given-size image at a short distance from the
screen. Short-throw projectors let you throw a large image in tight spaces, and
also minimize the risk of people getting in front of the projector and casting
shadows. There are no universally accepted definitions for what counts as a
short throw, but as an example, where most projectors can throw a 2-meter-wide
image from roughly 12 to 15 feet, most short-throw projectors need 3 to 6 feet,
and ultra-short-throw projectors need only inches.
A wide and ever-growing range of business projectors are
available, but you needn't get overwhelmed by the variations. Once you
understand what differentiates them, you're sure to find at least one, and more
likely several, suitable models to choose from.
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