The Right Projector Screen Can Save You Money
by: Nick Summers
How can picking the
right projector screen save you money?
One of the biggest
challenges when choosing an lcd projector is getting
the right brightness for the room you are going to
be using it in. For home use you can usually darken
the room. This means you can buy a cheap lcd
projector, often saving many hundreds, if not
thousands, of dollars.
But often darkening
the room significantly is neither possible nor
desirable. Buying a higher specification projector
will give you a brighter image, but it's probably
cheaper to buy a high gain projector screen. The
quality lcd projector may cost you a thousand
dollars more than a dimmer model, whilst quality
projector screens that enhance the image brightness
and clarity are only a few hundred dollars more.
Brightness and Screen Gain
The brightness of
an lcd projector is given in ansi lumen. Typical
values for home theater and business presentation
use are 500 to 3000. The higher the number, the
brighter the picture will be. At the low end a
darkened room is essential, whilst at the very top
end acceptable results are possible with higher
light levels. The current generation of home use
projectors are typically in the 1000-1500 range.
The gain of a
projector screen is the increase in brightness of
the image produced compared to a flat matt white
screen. This is given as a simple number, eg 1, 1.5,
2 etc. A gain of 1 means the image is the same
brightness as on a flat matt white surface, whereas
2 means the image is twice as bright.
As an example, if
you decide you need about 1500 lumen to get an
acceptable quality picture, you could buy a
projector with that rating and worry about the
screen later. Or you could buy a cheaper 1000 lumen
model and match it to a projector screen with a gain
of 1.5. This would give you an effective image
brightness of 1500 lumen at a reduced cost.
Very High Gain
projector screens have gains of between 1 and 1.2.
Gains of 1.5 to 1.8 are achieved with high quality
perlescent finishes at about double the cost. If
money is no object and you need the maximum gain
possible then you need a chromatically matched
Gains of up to 4
can now be achieved with matched projectors and
screens. An lcd projector only transmits 3 narrow
wavelengths of light in Red, Green and Blue. A
matched projector screen is covered with material
that reflects only these wavelengths. Almost all of
the ambient light is absorbed or scattered, so the
projected image appears very much brighter.
The Downside of
High Projector Screen Gain
screen gain might help you use a cheap lcd projector
in brighter rooms than it could cope with on its
own, there are 3 trade-offs. These are the viewing
angle, color shifting and uneven brightness.
High gain projector
screens limit the viewing angle. For a screen with a
gain of 1 the picture appears high quality out to
about 50 degrees from the projector. But at a gain
of 1.5 that viewing angle is reduced to about 35
degrees. Over 2 and the viewing angle is down to
around 25 degrees, making it much more difficult to
layout your room.
happens due to the surface properties of the higher
gain screens. A true white screen will render colors
accurately. By trying to manipulate the way light
reflects, a high gain screen can cause a shift in
some of the colors. This is rarely a reason not to
buy, unless you really do need the colors to be spot
The biggest impact
a high gain projector screen has on image quality is
the change is brightness from the center of the
screen to the edge. There can be up to 30%
difference at gains over 2. This is usually not too
much of a problem, but it does become far more
noticable the higher the viewing angle.
A little research
and a bit of leg work could help you make great
savings. Treat the projector screen as an integral
part of your system and buy it together with your
projector. Visit stores and insist on demonstrations
with a variety of lcd projector and screen
Choosing a good
quality, moderate gain (1.4-1.6) projector screen
can decrease the cost and increase the performance
of your system. A cheap lcd projector can produce a
bright, clear image at higher than expected light
levels. So whilst your projector screen may cost
more, overall you save.