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jerry wass
January 31st 08, 08:50 PM
Why does the diameter of the reflector have so much effect on the
output-(candlepower)--of bulbs having the same power input?? i.e.
#4509-PAR-36 4.45"Ø 110,000cp
#4537-PAR-46 5.70"Ø 200,000cp

And then we have the newer import cars using 2.5" reflectors (+ a
condensing lens of similar dia.) which are apparently equal to the
larger rectangular bulbs of conventional design.

then there are the hand lanterns with QH peanut bulbs of 50 to 100 watts
boasting 500,000 to 1,000,000 cp. Jerry

Gig 601XL Builder[_2_]
January 31st 08, 09:15 PM
Jerry Wass wrote:
> Why does the diameter of the reflector have so much effect on the
> output-(candlepower)--of bulbs having the same power input?? i.e.
> #4509-PAR-36 4.45"Ø 110,000cp
> #4537-PAR-46 5.70"Ø 200,000cp
>

The reflecting area is larger. 15.55 in^2 compared to 25.51 in^2

jerry wass
February 1st 08, 01:00 AM
Gig 601XL Builder wrote:
> Jerry Wass wrote:
>> Why does the diameter of the reflector have so much effect on the
>> output-(candlepower)--of bulbs having the same power input?? i.e.
>> #4509-PAR-36 4.45"Ø 110,000cp
>> #4537-PAR-46 5.70"Ø 200,000cp
>>
>
> The reflecting area is larger. 15.55 in^2 compared to 25.51 in^2
>
>
#4559-PAR-64 8.1"Ø= 600,000cp-(with 600 watts input)
would this equate to 100,000cp- (with 100 watts input)?--
Yet it's area is 51.5 1n²--or nearly 3.31 times as big as the 4509.

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