Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!think.com!mck-csc!jw From: jw@mck-csc.mckinsey.com (Jeffrey Weiss) Newsgroups: sci.electronics Subject: Re: heat of home vs. theater halogens (was: Do [they] need ballasts?) Summary: Why are you suspicious? Keywords: halogen Message-ID: <1990Dec6.181857.4568@mck-csc.mckinsey.com> Date: 6 Dec 90 18:18:57 GMT References: <1990Dec3.183744.9175@xrtll.uucp> Reply-To: jw@mck-csc (Jeffrey Weiss) Organization: McKinsey & Company, Inc., Cambridge, MA Lines: 21 rsnider@xrtll.UUCP (Richard Snider) types: >Lastly, I am suspicious in general of many of the "indoor" halogen >types of lights. To get maximum "light for the buck" a halogen bulb >must be run a LOT hotter than the ones I see in stores are. Specifically >I have done quite a bit of theater lighting using lots of halogen >equipment, and usually when a light is on full, in order to get >proper re-deposition the quartz tube will glow bright red. It will >also keep glowing for several SECONDS after the light is shut down. I'm trying to understand this. I have two different types of halogen fixtures at home. One is by LSI (seen mostly in stores, malls, etc.) that uses 12V 75 watt MR-16 lamps. The others use 12V 50 watt small bulbs. Both of these glow for several SECONDS after the switch is thrown. This is the reaction I have seen most often with all halogen fixtures I've had a chance to turn on and off. I have a hard time figuring out what color the tubes glow when at full power since (even at these modest wattages) I can't look directly at them without going blind! For what reason would these lights be run not hot enough? -- jw@mckinsey.com (...mit-eddie!mck-csc!jw) Jeffrey Weiss