Film-Tech Forum ARCHIVE: Angle Effect on Bulb

This is topic Angle Effect on Bulb in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Bill Enos (Member # 440) on 10-26-2004, 06:53 PM:

What effect does our 14 degree projection angle have on xenon life and stability. 3000W at 93 amps Superior, rotating at 250-300 hrs. in Kneisley 4000 watt lamp with 2 blowers, one on each end of the bulb, more than adequate exhaust.

Posted by Mark Gulbrandsen (Member # 72) on 10-26-2004, 08:27 PM:

Thats a bit of a down tilt and I'd be far more concerned about all the keystoning in the image.

To rotate or not..... I usually advise not to and have never seen any detrimental lamp life resulting. Lamp envlopes don't blacken like they used to before the "Getter" days and the electrodes are much more stable over time as well. With the lamps left alone I have customers getting 13K hours regularly with Christie 2K lamps(not by my choice!). This way the relfectors, blowers and other stuff gets attended to by a real technician instead of a booth mongral. I suppose to rotate or not is good subject for another thread......
We have a 6 screen drive in here in town that runs 4K Christie lamps to about 4K hours without rotation. Go figure.......

Mark @ CLACO

Posted by Ian Joseph Parfrey (Member # 2682) on 10-27-2004, 05:07 AM:

How would angle affect verticals, and what would the max angle be?

Posted by John Pytlak (Member # 331) on 10-27-2004, 05:31 AM:

The technical specifications for each lamp usually specifies the recommended range of angles from the horizontal or vertical, and whether magnetic stabilization is needed.