Dave Liquorice wrote:
On 15 Jul 2004 22:30:07 GMT, Ian Stirling wrote:

Seeing as the blackest black you get will be the intensity of the
white screen under your ambient lighting!

Easy, no ambient lighting. B-)

Even that's basically a lie.
You're going to get only a contrast of a few hundred at most in most
houses, as the light will reflect off the walls.

What light? I said "no ambient lighting" no picture from the projecter
you can't see your hand at all, not if when it touches your nose. ie
real dark, something that most people have never really experienced
these days. With light pollution, street lights, maintained emergancy
lights etc etc.

15000:1.
If the projector puts out 700 lumens, then on black, it produces
..05 lumens.
In other words, about the same amount of light as one of the brighter
(not superbright) LEDs, as used for indicators.
This is plenty of light to see by.
Not well, but it's plenty for a 'not fall over things' light.
With a 2.5m (across) display, it's about a tenth as bright as full moonlight.