Light Output Measurements

From CPFWiki

Lumens

Lumens is a measure of the total output from a light source. It's the human-eye-usefull part of energy : at the MAX sensitivity of mean human eye (555 nm, yellow-green), 683 lumens are equivalent to 1 WATT.

See Hotwire Math for re-rating formulas

MSCP (mean spherical candlepower)

MSCP is just another measurement of total light output. MSCP times 4 times pi = Lumens.

Carley Lamps lists output in MSCP.

Candlepower

Candlepower measures the intensity of a light source at a single point a given distance from the source.

You cannot convert from candlepower to lumens. It's like the difference between pomegranates and watermelons - with one, you eat the seeds and throw away the flesh, and with the other, you eat the flesh and throw away the seeds.

There are a number of units for measuring intensity:

cd - candellas (Candlepower)

mcd - millicandellas

lux (essentially the metric equivalent of a candlepower)