- (Guest Question!) - How powerful/much light does one give off? I suppose that since there are different sizes of theaters nowadays, there might be more than one “standard” bulb; just pick any of 'em. - MC
Good question, and you’re right about different sizes/wattages. Depends on size of projector lamphouse and screen, plus the distance (“throw”) between the projector and the screen. If I remember right, smaller theaters (100-300 seats) use about a 1000 watt bulb. Larger theaters (500+) use 4000 watt bulbs. They’re really hard to change because the glass is so delicate that you’re not supposed to get any oils from your fingers on the bulb, otherwise when the oil deposit heats up it will cause a hot spot on the bulb and it’ll burst. (I was standing next to a lamphouse once when the bulb blew and almost fainted in terror – you have no idea how loud that is!)
On a sorta similar subject: If you ever read Roger Ebert’s “Movie Answer Man” column he’s on a crusade to berate theater managers for turning down the amps in their lamphouses to make bulbs last longer. For the record, he’s barking up the wrong tree. In most theater chains the managers don’t even know how to change a bulb, much less turn down the power source and the savings would be questionable. If you’re seeing a movie that seems too dim the most likely explanation is that the bulb is nearing the end of it’s life and the manager is still waiting for the company technician to come install a new one.
Sarcasm detector? Oh, THAT’S a real useful invention!