CRT Primer
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Updated: April 2006 |
CRT Brightness
There is no question that CRT projectors require a dim or dark room for
proper viewing. While the image will look best in a pitch black room, a low
level light may be on without detracting from the image.
Fluorescent lights are
very bad for a video image as is sunlight or any light coming in from windows.
Neon signs such as bar signs tint an image terribly, and often a bar must
relocate such a neon sign when we install a projector.
Entry-Level CRT Projector: 600-800 lumens
Intermediate Level CRT Projector: 1000-1200 lumens
High Performance CRT Projector: 1200+ lumens
In general, most CRT projectors put out a minimum of 550 lumens, which is
adequate for a 7-8’ screen.
The brightest CRT projector that I know of has rated
at about 1500 lumens, which was the Barco 1001, but tube failure was common on
these and several other similar older Barco models. I do not believe that an
average home theatre needs more than 1200 lumens.
The larger the tubes surface, the more area there is to project an image on,
and in theory the slower a tube will wear out. Naturally, the larger tubes are
rated for more light output than a smaller tube, and thus a larger tube can be driven harder than a small tube. Hence, all picture tubes last about the same
amount of time (i.e. 10,000 hours) if you drive them as the manufacturer intends.
However, using CRT projector with large 9" tubes (1200+ lumens) on a smaller
screen size will result in your tubes wearing slower. It's not uncommon
for a 9" CRT tube to last 20,000 hours instead of the 10,000 hours you'd get out
of a 7" tube on on average sized home theater screen (i.e. 8' wide as seen in
the picture above).
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