quick question about lumen/watt ratio [Archive] - Green Grass Forums

socialinjustice

11-15-2006, 02:55 AM

ive read people saying go for watts but ive also heard many say go for lumens. right now i've got a little over 10,000 lumens outa 4 60 watt cfl's. will this suffice for veg.? im only going to be vegging till my plant is around 15 inches.

harris7

11-15-2006, 03:24 AM

well i support lumens and this is why:

watts is a measure of power
lumens is a measure of light

we care about how much light the plants get right...

as well, different types of bulbs have different efficiencies which means that 100watts for a HPS will be more light than 100W CFL. so it's not very accurate.
Efficiencies differ even within the same type of light say HPS, but between the different sizes. 600W being the most efficient. I wrote all about this somewhere on the forum

Anyhoo, you need a measure of area to find light intensity. you've only told me the total amount of photons you've got we need to know the area there hitting.

So you want to find lumens per sq foot. Very simple its lumens/area.
Check out my grow (link in signature) if you want to see some results for my intensity. Its somewhere around 5100 lm/sq ft for veg with a MH

later