Lumens, Lux, and Adding It all Up

Since the intensity distribution of wavelength is different for different color temperatures based on Wien's displacement law...shouldn't plants only need a single color temperature ie. 6500K for vegetation, and flower growth? Since that 6500K bulb emits wavelengths from 400-700nm, why would you need a 2100K bulb for promoting flowering if it gets the flowering wavelength from a 6500K bulb also? Someone please clarify this for me as I know this assumption is wrong.

AeroWRX said:

Since the intensity distribution of wavelength is different for different color temperatures based on Wien's displacement law...shouldn't plants only need a single color temperature ie. 6500K for vegetation, and flower growth? Since that 6500K bulb emits wavelengths from 400-700nm, why would you need a 2100K bulb for promoting flowering if it gets the flowering wavelength from a 6500K bulb also? Someone please clarify this for me as I know this assumption is wrong.

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Those are SUNLIGHT graphs not Fluorescent BTW
6500k dont produce an abundance of light over the entire spectrum....
this is a standard 6500k bulb spd

That is the GE "Daylight" bulb for 6500K using:
Using http://www.gelighting.com/na/business_lighting/education_resources/learn_about_light/distribution_curves.htm



How about this one for a "cool white" 4100K GE bulb? Still isn't too bad

AeroWRX said:

That is the GE "Daylight" bulb for 6500K using:
Using http://www.gelighting.com/na/business_lighting/education_resources/learn_about_light/distribution_curves.htm

How about this one for a "cool white" 4100K GE bulb? Still isn't too bad

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Those are halophosphors and they are discontinued... they had very low CRI and those SPD charts are VERY old....taken by even older spd light meters... they measured LUMINOUS FLUX not NM

ok so here's my situation:
I have 2 150 watt hps lights
I have 1 70-100 watt metal halide
I have plenty of reflectors, if needed
I have plenty of ventilation if needed
I have a 4 x6 grow room
I have 11 empty pots
I have 50 chronic seeds
I want to yield close to a pound if not more
I can do scrog, sog, or someother light training method
I could also just let them grow straight up
What height should I grow them to, how long should I veg, How should I place the lights to get the best yield? How many plants should I grow...basically tell me what I should do to get the best out of what I have...

HAHA IMHO fella's i would rather pay 60.00 bucks for 4 of these cfl bulbs which equals 16,800 Lumens: http://www.homedepot.com/h_d1/N-5yc1v/R-100676712/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053 rather then make a dumb purchase of a high watt MH and/or HPS that can burn me if i get too close? FUCK THAT! CFL CREW ALL DAY! FUCK WHAT ALL YALL HATERS SAY! LMFAO

I use the plug and grow system amazing spectrum and lumens output and have to agree CFL, made ma avatar pic

MrPotHeadDegree said:

HAHA IMHO fella's i would rather pay 60.00 bucks for 4 of these cfl bulbs which equals 16,800 Lumens: http://www.homedepot.com/h_d1/N-5yc1v/R-100676712/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053 rather then make a dumb purchase of a high watt MH and/or HPS that can burn me if i get too close? FUCK THAT! CFL CREW ALL DAY! FUCK WHAT ALL YALL HATERS SAY! LMFAO

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First of all, to get the best efficiency of your CFL bulbs, it's best to use 20w-40w bulbs. Especially 20w-26w.
CFL bulbs must be very very close, 1"-3" to achieve the best possible results.
MH/HPS systems are better for larger grows, larger spaces, more light penetration, and the simple fact that it's one lightbulb.

ok so im thinking of doing a grow in an area of 5x7 feet if i use a light rail mover (6'travel) and a cool tube what would the smallest hps light that you would recomend be

this is hardly the place to be talking about growing method... its about LIGHT not the source not the bulbs or the method but measuring light what defines lumens lux par pur and spd charts....

I found a lux light meter so I'm going to test my 1000 watt light. Not really sure what s hood reading for it would be in a five by give tent

From what I read lumens do not add up... if you have 2700 lumens in one bulb even if you buy 50 bulbs you'll still have 2700 lumens per square foot.

false... you read wrong.. next time u read something use a wiki page to research facts posted by others!

From another forum by gqmetalhead "Sorry to burst everyone bubble, but lumens DO NOT add together, at least not in the sense that 2 cfl's that output 2000 lumens will be as bright as a 4000 lumen cfl's. Contrary to popular belief, it's just not the way it works, you can have 50 2000 lumens cfls side by side and if you use a luxometer to measure the light output it will only measure 2000 lumens. On the other had you still will double the amount of photons and usable light the plant recieves, so all is no lost."

Someone is wrong... Love the Internet.. EVERYONE TELLS YOU THEY KNOW WHAT THERE TALKING ABOUT...

NO ONE DOES...

Bunsen and Roscoe’s law, expressed as H = l x t = constant, implies that exposure, (H), at a high intensity for a
short time (t), is the same as exposure at a low intensity (l) for a correspondingly longer time. 1000 lux for 10
seconds has the same effect as 10 lux for 1000 seconds. Or, as expressed by Stefan Michalski, “light effects are
cumulative in a simple additive manner”
The lumen can be thought of casually as a measure of the total "amount" of visible light in some defined beam or angle, or emitted from some source. The number of candelas or lumens from a source also depends on its spectrum, via the nominal response of the human eye as represented in the luminosity function.
The difference between the units lumen and lux is that the lux takes into account the area over which the luminous flux is spread. A flux of 1000 lumens, concentrated into an area of one square metre, lights up that square metre with an illuminance of 1000 lux. The same 1000 lumens, spread out over ten square metres, produces a dimmer illuminance of only 100 lux. Mathematically, 1 lx = 1 lm/m2.
A source radiating a power of one watt of light in the color for which the eye is most efficient (a wavelength of 555 nm, in the green region of the optical spectrum) has luminous flux of 683 lumens. So a lumen represents at least 1/683 watts of visible light power, depending on the spectral distribution.
read a book save a stupid question

From another forum by gqmetalhead "Contrary to popular belief, it's just not the way it works, you can have 50 2000 lumens cfls side by side and if you use a luxometer to measure the light output it will only measure 2000 lumens. I've actually witnessed a demonstration of this."

Me to "Professeur" - Your full of $hit

All you said in that math formula is NOTHING TO DO WITH ACCUMULATIVE lumens... Your just explaining a formula for something else and trying to sound smart.

Stop reading books and get a real education... I've read the same stuff you quoted.. BUT IT IS ALL IRRELEVENT because it doesnt address the question... The guy said he's witnessed it... I believe the results of the luxometer not random information that you copied and pasted from Wikipedia...

Congratulations at being an ass. You must be the next Einstein... Jerk. NOW IF SOMEONE can explain to me how I can stop BURNING THE HELL Out of my plant with these cfl's But I want to keep em close No hard feelings proff... I just dislike people bashing before giving the other person a chance...

curto said:

All you said in that math formula is NOTHING TO DO WITH ACCUMULATIVE lumens... Your just explaining a formula for something else and trying to sound smart.

Stop reading books and get a real education... I've read the same stuff you quoted.. BUT IT IS ALL IRRELEVENT because it doesnt address the question... The guy said he's witnessed it... I believe the results of the luxometer not random information that you copied and pasted from Wikipedia...

Congratulations at being an ass. You must be the next Einstein... Jerk. NOW IF SOMEONE can explain to me how I can stop BURNING THE HELL Out of my plant with these cfl's But I want to keep em close No hard feelings proff... I just dislike people bashing before giving the other person a chance...

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You obviously have no idea how light works.. of course you cant measure lumens with those light meters and cfl bulbs stupid!
light moves in every direction you would have to focus ALL of the light in 1"sq and measure it !!!! i hate how people use measuring intstruemts like monkeys with sticks!!! “Footcandles” and “lux” are units that indicate the density of light that falls on a surface. This is what light meters measure.
a bulbs prodiuces 1200 lumens for example... first your light meter measures LUX not lumens... LUX is the measurement of light @ the surface. 1 lumens = 1LUX per sq/m
So if you have 1000 which measures 10764 LUX : then measure the total area of the light lets say a CFL
lets say 10cm x 3 cm
total area 2*pi*r*(r+h) ~ 0.03 m^2
10764 lux * 0.03 m^2 = 327.5 lumens
your tryin to measure without taking into consideration that each bulb increases the total area of light by the same amoumt...
Required Light Output/Fixture (Lumens) = (Maintained Illumination in Footcandles x Area in Square Feet) ÷ (Number of Fixtures x Coefficient of Utilization x Ballast Factor x Light Loss Factor)
do i need to do all the math? you forgot to measure the total area / total fixtures...
do the math or shut thr *F* up! i have more education and literary knowledge to lead you to an answer
but like a horse i cant force you to READ THE FACTS... None of the "sources" you quote used ANY scientific method.
and bought a fancy toy without knowing how the fucking thing works... its idiots like you who drink whatever koolaid your given without evaluating the facts for yourself?
its called peer review for a reason... no one who did any of this work can use MATH to prove their results.. they rely on a piece of equipment NOT designed to measure total lumens in an area... DUH!
heres a page from OKsolar that has some math from 9th grade... so you can understand it! There is only one cure for ignorance! but there is no cure for stupidity!
http://www.oksolar.com/pdfiles/abc-tech_candela-lumen.pdf
then when your done read here to learn how to ACCURATELY measure light from a source with a REAL SCIENTIFIC INSTRUMET
NT!
http://en.wikipedia.org/wiki/Integrating_sphere

Alright I give up... I just wanted to know who was right and who was wrong.. I really don't even care, other then I wanted to know who was wrong...

So thanks for explaining.... May have to read this again tomorrow when I'm more interested.. But it's good were getting the info out..... Good work and sorry for being a little up front.. It's just your first response was uncalled for... I'm not going to read a book just to find something out that doesn't even matter in my life and by the time it does matter I'd probably forget it. (traditional education can really, really, suck me.... Who can remember the most during a 3 year period graduates!)

It's much better to make a quick confrontation with someone about the question... THEN I REMEMBER IT...

curto said:

Alright I give up... I just wanted to know who was right and who was wrong.. I really don't even care, other then I wanted to know who was wrong...

So thanks for explaining.... May have to read this again tomorrow when I'm more interested.. But it's good were getting the info out..... Good work and sorry for being a little up front.. It's just your first response was uncalled for... I'm not going to read a book just to find something out that doesn't even matter in my life and by the time it does matter I'd probably forget it. (traditional education can really, really, suck me.... Who can remember the most during a 3 year period graduates!)

It's much better to make a quick confrontation with someone about the question... THEN I REMEMBER IT...

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Remember that these people posting this dribble have supposedly invalidated the laws of physics and math with a LUX meter? sounds fishy check their MATH!