Screen Technologies...
Front projection screens have been offered in a variety of materials as
technology changes over time. In the past, screens were offered as
glass beaded or pearlescent surfaces, to help boost the brightness of low
powered projectors. However, these surfaces were shown to have their
limitations. Grey projection surfaces were also popular to boost
blacks which LCD projectors had difficulty reproducing. Now, new
'black' screens have arrived which offer brighter images in rooms with
higher ambient light.
Matte white screen material is currently the best choice for modern
projectors in darkened cinemas or home theatres.
Black projection surfaces are best for modern high powered projectors in
rooms with high ambient light.
In a darkened room, matte white ensures:
- True colour reproduction.
- Highest possible resolution capacity.
- Widest possible horizontal/vertical viewing angle.
- No glare and no hot spotting.
- Can be washed if soiled.
But, in high ambient light, a black
projection screen offers the best images.
Other screen materials will compromise image quality in one way or another to
increase the screen's gain:
Grey screens - There has recently been a
lot of marketing hype about grey front projection screen materials which improve
contrast. Unfortunately, with front projection, this results in a colour
shift to the blue spectrum - not a problem with black and white projectors but
can produce unexpected results with colour, particularly skin tones.
Glass beaded screens have a higher gain
however you will experience a dramatic loss of viewing angle and a loss of
resolution. Glass beaded screens are retro reflective, that is their
preferred direction of reflection is to the light source. With a ceiling
mounted projector, the brightest image is under the ceiling........ hardly the
place to watch your DVD or videos. They are also mechanically unstable in
that the beads can move or fall off entirely, creating very distinctive dark
spots.
Pearlescent screens have a higher gain,
however colour shift to red occurs and there is a tendency to hot spot.
They also have a narrow viewing angle, are not readily available and expensive.
In summary:
- Dark Room = Matte White Screen.
- Light Room = Black Screen.
See the
Links section for some examples of good Matte White or Black Projection
Screens.
|