Tech Talk
Answers to users' most
common questions about Projectors
Most recent projectors
include video inputs for HDMI (High-Definition Multimedia Interface), a
computer input (either DVI [Digital Visual Interface] or VGA [Video Graphic
Array]), and component.
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What are a
projector’s key specifications concerning image quality?
The two key specifications
for image quality with projectors are resolution and brightness. Resolution is
the physical number of pixels used to create the on-screen content. You'll see
resolution expressed with two numbers, such as 1,920 x 1,080. The first number
is how many pixels run from the left side to the right side, while the second
number covers the top to bottom pixels. The higher the resolution, the more
detail you'll see in the projection, which is important for those that have
presentations with text, graphs, and video.
Maximum
resolution and brightness are two of the most important specs when it comes to
a projector's image quality.
Brightness is measured in
lumens. The more lumens, the brighter the image the projected image will appear
(note that you can lower the brightness, if necessary). Most any projector will
look good in a dark room, but the amount of lumens comes into play when you use
a pro¬ jector in situations where the lights won't be turned off, such as at a
board meeting or when performing training. In short, a projector that offers a
greater number of lumens than anoth¬ er can be used in a wider range of venues
and provides you with the flexibility to adjust the image to room conditions.
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How will I
know if a projector will display a size that works in my environment?
Typically, a projector
manufacturer will list the throw distance (range of space between projector and
screen), such as 4 feet to 95 feet, as well as the span of screen sizes the
projector can accurately deliver. The zoom lens built into the projector will
allow you to adjust the size of the image to best fit the wall or projection
screen, while the focus controls allow you to adjust the image for crisp
detail.
You
can use the projector's focus and zoom controls to fit the picture to the
screen.
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What types
of image correction are available to shift the picture when the projector isn't
situated perfectly in the room?
There are two types of
image correction you'll need to know about; lens shift and digital keystone
correction. With lens shift, the projector can alter the position of the lens
to move the projected image slightly up or down (vertical lens shift), and some
projectors can also adjust the image to the left or right (horizontal lens
shift). Digital keystone correction is used when the projector isn't lined up
perpendicular to the screen, which causes the image to appear more trapezoidal
than square. If you can’t shift the lens to accommodate the location, keystone
correction scales the image before it reaches the lens, so it will end up
looking square on the wall.
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What is a
Pico projector?
The
MicroVision SHOWWX+ ($369; www.microvision.com) is a pico projector that works
with any HDMI-equipped smartphone, tablet, or laptop.
It's a handheld projector
that's de¬ signed to project images from your portable devices, such as
smartphone or laptop, for a small viewing audience. These lightweight
projectors can generally fit in a pocket, so they're great for business
travelers who need a projector with them.
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What of
devices will I be able to connect to the projector?
Projectors
offer inputs for all different types of devices.
Most recent projectors
include video inputs for HDMI (High-Definition Multimedia Interface), a
computer input (either DVI [Digital Visual Interface] or VGA [Video Graphics
Array]), and component. Thus, you'll be able to connect a wide variety of
equipment to the projector. Before purchase, ensure that the projector offers
inputs that match the video output of your devices. A few audio inputs are also
generally included, assuming the projector features built-in speakers.
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What is the
typical lifespan of a projector lamp?
Most current projectors
come with a lamp that will operate beyond 3,000 hours in its brightest mode.
Projectors will often provide you with a lamp life rating (in hours) for
multiple display modes, such as Eco (long lamp life) and Standard modes.
