Replies

1. 
   JohnK | Nov 24, 1999 06:27pm | #2

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   Rockford,
   We have MH in our factory. I love them. Our's are hung about 15 ft. high and 15 ft. apart. They have the "clear" shades that let some light go up and bounce off the ceiling.
   This gives a much more even lighting. They're about 5 yrs. old and we've probably relamped about 10% of them. The light is white and color rendition is good. (we've got low pressure sodium outside that are cheap but pink) The only negative is they take a few minutes to start. Good Luck, John

2. 
   Dennis_Argazzi | Nov 25, 1999 12:30am | #3

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   Rockford: Different metal halide bulbs produce different "colors" of light. The "color" of the light is usually expressed as a temperature in degrees Kelvin. Metal halide bulbs are available in color temperatures from under 3,000 deg.K to over 10,000 deg.K. Under 3000 deg.K produces the yellow to pink light more typical of sodium bulbs. At about 5500 deg.K the "blacklight" glow, Ryan mentioned will become noticeable. For general overhead lighting, bulbs with a color temperature around 4000 deg.K should be fine, especially when combined with fluorescent or incandescent task lights.

1. 
   bakdo_ | Nov 26, 1999 06:12am | #4

   *MH lights are great if you have the time to wait for them to fire and pay the initial cost.

3. 
   Guest_ | Jan 04, 2000 11:44pm | #5

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   I'd like to get some feedback on using low-bay type metal halide fixtures in a residential garage/workshop application. The area is 19' X 44' with 10' plates. I would anticipate the plane of the fixtures to be at about 12 to 13 feet above the concrete floor. A rough calculation shows that I can use three 175 watt metal halide fixtures for the area.

   Are these fixtures going to yield too much light? Will they temporarily blind me when I look up? Will they generate too much heat to the point where they would be uncomfortable to work under?

   Any experience, pros/cons, or alternatives would be appreciated.
   Thanks!

1. 
   Guest_ | Nov 24, 1999 07:20am | #1

   *None of what I'm about to say is based on any figures, tables, or any "official" rules of thumb, just my experience.Metal Halides are a harsh light. Expect whites and other light colors to glow as if they were under a black light. (not as brightly though)Everything takes on a purple glow.They are great for lighting large areas and keeping electrical costs down.Three fixtures in a 44' long space will give harsh shadows.As far as heat, MH lamps generate less heat per lumin than incandescents. Quite a bit less but as I said, I didn't bother to look any numbers.Blinding? yes but if you don't look up, no problem.I'd suggest fluorescent lights. Cheaper (alot), softer light, similar electrical bills. For the cost of three MH fixtures with bulbs, you could probably get 10 fluorescent fixtures.