What's The Difference? .... Metal Halide Question

[luckyinkentucky]

What's the difference between regular Metal Halide bulbs and Ceramic Metal Halide Bulbs?

I'll be using them in the 400w range for my Wobble Light, and didn't know which replacement bulbs to get. It would be a headache and a $30 mistake if I got the wrong one.

Thanks.

 

[Richie086]

What's the difference between regular Metal Halide bulbs and Ceramic Metal Halide Bulbs?

I'll be using them in the 400w range for my Wobble Light, and didn't know which replacement bulbs to get. It would be a headache and a $30 mistake if I got the wrong one.

Thanks.

I thought the ceramic version is what's in use today in our HID flashlights.

 

[flashguy]

the ceramic ones i know mostly have a built in reflector. i don't know much about this kind of bulbs but maybe someone else?

greets,

flashguy

 

[65535]

AFAIK the only difference is a quartz arc tube vs. an alumina based arc tube. I would imagine the alumina ceramic tube would give a more diffused nicer output, but I don't think it physically matters for the same size bulb.

 

[brickbat]

The use of a quartz arc tube precludes the use of certain halide salts, as they attack the quartz and diffuse through the walls. Ceramic arc tubes don't allow this diffusion to happen, so the choice of salts that can be used is broader, and consequently, better color rendering can be achieved.

Further info here:

http://www.lamptech.co.uk/MBI Ceramic.htm

PS: make sure the lamp you select is rated for your ballast type. Some CMH lamps need different ballasts than an equal wattage quartz lamp