2,000,000 lumens with practicaly no heat?

[beardo]

hi im new to all this, been lookin round this site for a while and i must say im impressed, theres some exceltent systems in here and most of you seem very helpful/friendly. im thinkin of trying to make a projector myself so will proably be asking lots of silly questions along the way and hope not to be to much of a pain


anyway heres my first question ...

could a torch like this be used inside a projector, its stupidly bright, relatively cool and has a focused beam, is this not a dream come true?

http://www.innovations.co.uk/gus/pr...ra=&mscs_sid=CCRFF3NTAD9J9NN10CK5EW823NQ22032

thanks in advance and happy to be here.... beardo

 

[slikk]

Hi Beardo and welcome to the board.

I remember someone posted on the topic of "candle power" and that it is not the same as lumen.

Here's a quote from Undream's post.
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We have already discussed these handheld spotlights you are posting about a few pages back.

We have also already discussed candlepower, and how it is not significant to the brightness of a light -- but rather the intensity of the beam produced. Candlepower ratings are VERY misleading. candlepower is merely the intensity of a light at a certain point. If you take a 100W halogen bulb, and put it on a reflector, the candlepower of the narrow beam produced is much, much more intense than if you took that same exact 100W bulb, and put it in a glass sphere, and measured the intensity of the light at a certain point outside the sphere.

This Mean Spherical Candle Power (MSCP) is the important number, and, THAT number is almost NEVER given on these "2 or 3,000,000 candlepower spotlights." If you had the MSCP number of the light, then, you would be able to take it, and convert it to lumens. What you CAN'T do, is take the false 3,000,000 candlepower number and convert it to lumens. That would be 37,000,000 lumens -- and we all know that a 100W halogen will probably produce at MAXIMUM 4,000 lumens (and thats being very generous)

I've seen the 2,000,000 candlepower light made by the same company that makes that 3,000,000 one at K-Mart, and, I was actually thinking about picking it up for $34.99, since, I would at least be able to use it for testing, and, also, the reflector in it is probably really cool. Its 6" diameter, and has one 100W Quartz Halogen bulb I think (burns whiter than regular halogens)

See this PDF for candlepower reference:

http://www.caves.org.uk/led/foot1.pdf

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