Lumens/Light Intensity question;

So I've been reading for a while about light intensity.
I've heard people measure Initial lumens 30" from the bulb, but I've also heard 12".
So which is the standard distance for lumens?
If a 23w bulb has 1500 lumens @ 12", does this mean that it has 6000@6", 24000@3", and [email protected]"???????

And if they measured it @ 30", would that mean 380000+ lumens @ 2 inches away?

Are our bulbs stronger than we thought?
Please, smoke a bowl and contribute, but keep things tidy.

Bump, I don't usually ask crazy questions like this, but it could seriously change CFL grows as we know it if this is true..

gngfjhjhm,vhj

As someone with much experience (both failure and success) with CFL's, I can promise you that people are not getting more CFL light than thought necessary. Rather, people don't have enough light, and in too many cases still don't put the bulb right up on the plant within 2" of the foilage. And they are paying for it in their yields and bud density.

If your information had any merit to it, newbies would be kicking ass with CFL's despite have less light than recommended. And they most certainly are not!

But according to the inverse square law, don't these numbers make sense?
The only unknown variable is how far from the bulb do CFL testers measure the lumens?

The inverse square law is only perfectly correct for a point light source. Any real light source in a grow room situation cannot be approximated to a point source. In most cases, your intensity will drop at a rate closer to 1/r. You can use your light meter to verify this. This doesn't mean your lumen production goes to infinity at the bulb center; the total lumen production is constant (approximately the number on the box) and what varies is the intensity (lumens/sqft.) since the light is spread over a larger area the further you get from the bulb/reflector.

HID systems are more efficient (lumens per watt) than fluorescents, but they produce more heat as they have a filament burning at several thousand degrees.

Oh, makes more sense.
Got my hopes up.
Thanks