Mercury Vapor Temperature

[Jonathan Bryant]

What is the color temperature of the blueish Mercury Vapor lights found in most big box stores? And what CTB gel recipe is needed to match tungsten lights to them?

[David Mullen ASC]

I find them similar to Cool Whites, which on a tungsten lamp require something like 3/4 Blue + 1/2 or Full Plus Green (the greeness varies amoung fixtures.)

[Michael Nash]

Many "big box stores" actually have Metal Halide lights, which is a variant of Mercury Vapor. I point this out only to distinguish these lights from the cheapo Mercury Vapor security lights available at hardware stores, which are significantly more saturated in color. There's a good description here.

 

And David's right; they're basically the same color as cool white fluorescents (blue + green), but at varying color densities depending on the type of light. In practice you still have to test different gel combinations to find the right color match. A digital still camera or color temperature meter helps with this.

[Richard Andrewski]

Mercury vapor color temp is around 4200K and CRI in range of 50.

 

All these things are HID variants and all use mercury (or sodium) but the ones called "mercury vapor" (and sodium vapor) are a monochromatic light that's not terribly usable for serious lighting unless you absolutely have to. The difference between a "metal halide" and a "mercury vapor" is that the metal halide has some additional iodine salts of other metals that the mercury vapor doesn't have. Even HMI is a member of the metal halide family and it too has mercury vapor in it along with a very high quality of metal iodine salts.

Edited September 22, 2007 by Richard Andrewski

[Vladislav Simeonov]

:rolleyes:

What I found on the Internet (My English is not good..Sorry)

color rendering index

color temperature

and This