Hmmm
Very interesting measurements. If you have a light that puts out 8900 lumens at 1 foot, that is the standard distance for a lumen by definition, and something doesnt work out here. Using the equation E=I/(d^2) with I being lumens and d measured in ft and I being the measurement you took at 2 inches we can work the equation using your measurment as E.
Here is what you get.
E=20,000(foot candles)
d=2in/12in/ft=.16667ft
and I= 20,000*(.16667^2)= 555 lumen.
There you go your 90 dollar bulb is a standard CFL bulb provided you used the light meter right. I doubt you screwed that up as 2 different people on this board measured that the same number. Something is not quite right?
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