A Very Important Fact About Lighting For Your Plants

I can't believe I'm taking the time to respond to this troll, but I will do so anyway.

King Cobra said:

Totally untrue- the 2 x 10,000 lumen bulbs will only give 10,000 watts per bulb and in that 4' square they will be 2 bulbs giving out 10,000 lumens each, thats their intensity no more or no less, it does not matter if the bulbs are right next to each other!! The areacthat the bulbs are shining on has a maximum intensity of 10,000 lumen. Common sense!! You just can't add up the lumens and say the amount they add up to thats just stupid -sorry-.

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Just to be clear, lumens are not the same as watts.

Simplifying a little bit, the term lumens refers to quantity of light perceptible to the human eye, divided by unit spherical area ("steradians"). Edit, see below

So you better damn well believe that if you double the point source of light, you're doubling the amount of light per unit area, and therefore the lumens.

If you want to make an appeal to common sense, shall we actually try one?

Lets say you have one light bulb on in your room. If more light bulbs won't make it any brighter, than why do people put more than one light in their rooms?

Why do candleabras and such have more than one light? Why do fluorescent light fixtures typically come in double-rows?

If there is no difference in total light output between one bulb and two, then why does your car have two headlights?

I could go on all day, but to summarize, even though each light bulb is equal to the other TWO light bulbs *DO* in fact, put out twice as much total light as one.

Edit: Sorry , that's lumens = light output x steradians, which is a 2d angular measurement somewhat akin (but not exactly) area. Regardless, the above is still true. Double the number of bulbs = double the light intensity in the same area = twice as much light for your plants to grow. This is why anyone who has actually tried it will tell you that more bulbs = more light = more plants.

The amount of spelling mistakes in this whole thread makes me sad.

King Cobra said:

This also alpplys to you, lmfao at you right now!
Basically if a light bulb states that it has 1700 lumen output then thats all the light will produce no more than that. So i will repeat myself yet again -- if you have 10 of them bulbs you will have ten bulbs with an out put of 1700 lumens each NOT a combined lumen of 17000. What you have just copied and pasted with out understanding was, the way in which lumens are worked out for different bulbs!

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Repeating this nonsense again and again doesn't make it correct. By the formula YOU quoted:

lm = candela X stereroradians.

If you double the number of bulbs, you double the candela output, and double the lumens.

10x the candelas = 10x the lumens, etc.

Now, bluntly, I don't know if you actually ARE so stupid as to believe the nonsense you just posted above, or if you're acting this stupid for trolling purposes, but I'd hope for the sake of the human race, that its the latter.

Either way, I'm done with you.

Good luck lighting up your garden with one 23W bulb!

I don't even follow this anymore..."I've decided you don't need lights to grow inside anymore"

that's what you sound like Senor Cobra

Originally Posted by King Cobra
This also alpplys to you, lmfao at you right now!
Basically if a light bulb states that it has 1700 lumen output then thats all the light will produce no more than that. So i will repeat myself yet again -- if you have 10 of them bulbs you will have ten bulbs with an out put of 1700 lumens each NOT a combined lumen of 17000. What you have just copied and pasted with out understanding was, the way in which lumens are worked out for different bulbs!
Repeating this nonsense again and again doesn't make it correct. By the formula YOU quoted:

lm = candela X stereroradians.

If you double the number of bulbs, you double the candela output, and double the lumens.

10x the candelas = 10x the lumens, etc.

Now, bluntly, I don't know if you actually ARE so stupid as to believe the nonsense you just posted above, or if you're acting this stupid for trolling purposes, but I'd hope for the sake of the human race, that its the latter.

Either way, I'm done with you.

Good luck lighting up your garden with one 23W bulb!


You stupid idiot! You have not read my post, well maybe you have but are too stoned to actually take it in. I have made a few spelling mistakes as iam not writing this on a pc amd frankly cant be bothered to correct them as it is too much hassel on this device. Take whatever you like from my posts, but from your last comment you really proved to me that you have no fucking clue!! I dont grow weed at all, in fact i rarely smoke it! But what i do is science and thats not even needed for this simple lighting question!

IslandDelight said:

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just do everybody a favor and do your occasional smoking and non existent weed growing elsewhere CobraCock[/QUOTE]

its king cobra and ill do what ever the hell i want! I posted some free precise advice today and most of you just slated it and put me down, if thats a community you like to belong to then its your loss and thats why the government keeps fucking you up the asses and you just let them do it, because most of you are sheep!! And just like to follow each other!!.

its ok...you'll live, because you are surely a wolf
farewell CobraCommander

WRONG....put your two six hundreds side by side...were the light overlaps there is more...very simple experiment...so ...the op is just wrong!

Wait, so I can put 10000 plants into a giant warehouse with a single 1kW lamp and grow the same amount of pot as with 1000 1kW lamps?!

I'm sold! Where can I purchase your technology that defies physics? A single light that puts out equal umol of PAR radiation as many many equal wattage lamps?! Please send me a link to purchase this product!

Gastanker said:

Wait, so I can put 10000 plants into a giant warehouse with a single 1kW lamp and grow the same amount of pot as with 1000 1kW lamps?!

I'm sold! Where can I purchase your technology that defies physics? A single light that puts out equal umol of PAR radiation as many many equal wattage lamps?! Please send me a link to purchase this product!

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tesla would be proud...lol

It works kind of like this. Say you have a laser that is visible at 1 mile. You shine it 1 mile away and you see a dot. Now you take another similar laser and shine it at the same spot 1 mile away - Whoah! The dot is twice as bright!

Now you take a laser that is visible at 2 miles. You shine it at a point two miles away and you can see it! Now you take the two 1 mile lasers and shine it at the same point - you can't see a dot

Even though you put two lasers together that are each visible from 1 mile away, it doesn't mean the two together are visible from two miles away. But if you shine them at the same spot 1 mile away the spot is twice as bright.

Lumen is measured from a single point and does not change with additional bulbs as by definition it is the measure of a single point of illumination (duh); Lux (lumen/area) does increase.

If light A produces X photons of energy and light B produces Y photons of energy then light A + light B = X+Y # of photons... It's one of the most widely known rules in physics - conservation of mass and energy.

So here is the deal.

The "facts" that King Cobra is posting are correct, in form. The key here is to understand exactly what those facts are telling you, and consequently that is the reason his thinking is incorrect. His facts are not incorrect he has simply misunderstood what they are actually telling him.

The fact that lumens are not additive "does not mean" that adding more identical bulbs to a grow will not increase your quality and quantity (with in reason). What it actually means is that it will not increase your penetration much. it also means that were all the lights originating from the same spot they would degrade identically as you moved further and further away from the source, where as a higher out put light would degrade slower as your move further away from it. There are in fact MANY benefits to adding more bulbs of the same type to a grow.

I'm not sure if my explanation will actually help and after rereading it much of it does sound ambiguous and hard to understand but i hope it at least clears up the point.

What King Cobra said is his original post about lumens and watts is all correct, however he has misinterpreted the translation of effects on reality.

IC3M4L3 said:

http://www.ebay.co.uk/itm/LX-1010B-Digital-Lux-Meter-Photo-Light-Meter-Lumens-Test-/360408430812?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item53ea0438dc


buy one of these and show us it under 1 light then both lights at same time,,,proove your theory

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This test was done in another thread on this forum. In the first post of the following thread the op makes 5 points. The 4th point is that the light intensity does accumulate and the 5th point shows the proof. Check it out.

https://www.rollitup.org/indoor-growing/83128-lumens-lux-adding-all-up.html

to put it simply if the over lap of two similar lights has more intencity than the areas not within the overlap footprint then it proves without a doubt u can stack lumens...of this im convinced...ive also used par lighting in a similar set up (non controlled) and seen posative and repeatable results.....

richinweed said:

to put it simply if the over lap of two similar lights has more intencity than the areas not within the overlap footprint then it proves without a doubt u can stack lumens...of this im convinced...

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In the end this is may all be a vocabulary issue i think. The term lumen seems to be causing some confusion. no you can't stack lumens, however the effect your are describing is true you are just using the word lumen in a way that doesn't seem to apply to it. Or maybe i'm confused.....idk

The lumen (symbol: lm) is the SI derived unit of luminous flux, a measure of the total "amount" of visible light emitted by a source. Luminous flux differs from power (radiant flux) in that luminous flux measurements reflect the varying sensitivity of the human eye to different wavelengths of light, while radiant flux measurements indicate the total power of all light emitted, independent of the eye's ability to perceive it. (http://en.wikipedia.org/wiki/Lumen_(unit))


This might be a good way to think of it.

if you were trying to describe the smell of some dog shit in your floor and you said it smells like onions (just for example) then you add another dog shit that is exactly the same to your room. now the stink is worse (stronger) but it doesn't make it smell any more like onions than it did before.

actually i think i give up, i'm getting more and more confused the more i try to think of a way to explain it. LOL

Adding more lights helps your plants get more light, bottom line. it just doesn't change "some" of the characteristics of the light.

Gastanker said:

It works kind of like this. Say you have a laser that is visible at 1 mile. You shine it 1 mile away and you see a dot. Now you take another similar laser and shine it at the same spot 1 mile away - Whoah! The dot is twice as bright!

Now you take a laser that is visible at 2 miles. You shine it at a point two miles away and you can see it! Now you take the two 1 mile lasers and shine it at the same point - you can't see a dot

Even though you put two lasers together that are each visible from 1 mile away, it doesn't mean the two together are visible from two miles away. But if you shine them at the same spot 1 mile away the spot is twice as bright.

Lumen is measured from a single point and does not change with additional bulbs as by definition it is the measure of a single point of illumination (duh); Lux (lumen/area) does increase.

If light A produces X photons of energy and light B produces Y photons of energy then light A + light B = X+Y # of photons... It's one of the most widely known rules in physics - conservation of mass and energy.

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i think this might be the best explanantion i've ever heard on lumens! props gastanker.

wow this foolish OP has gotten a lot of feedback... so what if it doesn't get any brighter, the area of brightness increases with more bulbs.. i can't believe this guy gets more attention than an honest first time grower needing help...

so anyway can i use 40,000 candles to grow my girls........?