Using the chart below tell me if there is something wrong with my calculations.
If you take a measurement 1" from the bulb wouldn't you need to divide the reading by 144sq. in. to show what the lumens are over 1 sq.ft. at 1" from the bulb. Then you would need to figure out how much of the surface area of the light is shining directly onto the square foot of space you are measuring. You would then take this answer & multiply it with the sq.in. to lumen answer.
Here is an example.
A 95w EVL is approx. 36sq.in. 12"Lx3"W
56,700lumen@1"/144sq.in.=393.75x36=14,175 lumen at 1" over 1sq.ft. with a 95w EVL centered over the sq.ft measured.
You would need to test the lumens without a reflector for this to be somewhat accurate.
In other words we need to take into account how much of the surface area of the light is shinning on the light meter when it's only 1" away from the bulb. The above calcultion only works if you assume that the lumens your measuring at 1" came from 1sq.in. of the output of the bulb.
Lumens of 95w full spectrum EVL with reflector.
1' = 3,780 lumen
10" = 8,820
8" =11,340
6" = 15,120
4" = 22,680
2" = 37,800
1" = 56,700
Does this make any sense or am I just really high & up to late?
Later.
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