"Calab" wrote:

With all the talk about CFLs, incandescent bulbs and LED bulbs I was
wondering... Is there a device that can be used to objectively measure
the brightness of a light? Something I can use to compare bulbs in my
home, auto headlights, flashlights, etc?

You might compare the outputs of bulbs with similar light patterns with
Robert Wilhelm Bunsen's 1844 "grease spot photometer." Put a 3x5 card with
a grease spot between them and measure the distance to each bulb when
the spot disappears (when it is equally-illuminated from both sides of
the card.) The outputs are then proportional to the inverse square of
the distances. For instance, if the card is 19" from the CF and 21" from
the incandescent bulb, the CF's output is 100(19/21)^2 = 82% of the bulb's.
You might screw both lamps into 2-prong sockets plugged into Kill-A-Watt
meters to measure the power...

Bunsen blew himself up with explosive gases on a regular basis.
He also invented the Bunsen burner, after his lab tech Desaga
invented it, after Michael Faraday invented it :-)

Nick