How much light is too much.........?

MEANGREEN69

MEANGREEN69

Well-Known Member
BloodShot420 said:
both of those sentences seem to mean entirely different things...

i did a little bit more research... seems like the accepted number for highest sunlight intensity is 10,000 lumens/sq ft... the highest i've heard of anyone recording is 13,011.

by my count each 400w light should be producing 55K lumens, totaling 110K.

he's running with 4 sq ft of floor space... so thats 27.5K lumens/sq ft...

27,500 lumens / 10,000 lumens = 275% brighter (best case)
27,500 lumens /13,000 lumens = 211% brighter (compared to highest value i found recorded)

either way - its really bright - the pics i'm sure dont do it justice, because your monitor cant blind you ;-)

make sense now?
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thanks bloodshot for the research u have done;-)...yeah after takeing the pics i had to sit down my eyes/head hurt:sad:....but the babys love that light!!:bigjoint:....now i just got to wait tell i can clone them and see how many females i have..then ill start my "micro SOG grow" 3 plants every week!! bloodshot ur a koolcat if u ever come to vegas let me know and we'll pass the peace pipe around brobongsmilie...peace
 
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BloodShot420

Well-Known Member
MEANGREEN69 said:
thanks bloodshot for the research u have done;-)...yeah after takeing the pics i had to sit down my eyes/head hurt:sad:....but the babys love that light!!:bigjoint:....now i just got to wait tell i can clone them and see how many females i have..then ill start my "micro SOG grow" 3 plants every week!! bloodshot ur a koolcat if u ever come to vegas let me know and we'll pass the peace pipe around brobongsmilie...peace
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Haha... that reminds me - last time i had a connecting flight in vegas i sat right next to this kid about as old as me who i could tell was extremely baked... he dropped a couple strain names and i found out he was a grower... apparently i dont look like a cop ;-) i asked him about his system and we exchanged some pointers - he knew his shit, we kept it anonymous but he was cool... i couldn't stay long, but i did win $75 at a slot machine at the airport... enough to get some tacos from the bell ;-)
 
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BloodShot420

Well-Known Member
lol yup... A-town down



i'm pretty much allergic to my girls when they are growing... i wear latex gloves, respirator, long sleeve shirt, sunglasses, and a hat when im working... i prob look scary, but if i dont, i get a rash on my arms like i was playing in nettles or something...
 
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BloodShot420

Well-Known Member
this is what i have to do in there every few days... i have to really dig around in there which is why i need the arm protection... also, i wouldnt be able to get the smell off of me for days if i didnt wear that shit...

anyways, here is a before and after pic... trying to keep them under the screen, and bring out the bud sites...



and here is the uv light locations... set to turn off if the door is open (thanks to the PLC) ;-)
 
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BloodShot420

Well-Known Member
i can get about 2 Ps in every 3 months using feminized beans (i dont have a mother/clone spot)... two 1K lights in vented hoods (ballasts vented too)..

using all advanced nutrients this time...

i'm getting a co2 tank and monitor for the next run... this time, i'm pulling air out of my office (where i work all day) so hopefully i'm providing enough co2... i might have to start doing a workout or something for them lol ;-)
 
TRICKKY

TRICKKY

Well-Known Member
BloodShot420 said:
by my count each 400w light should be producing 55K lumens, totaling 110K.

he's running with 4 sq ft of floor space... so thats 27.5K lumens/sq ft...
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Just a heads up lads, if each lamp is producing 55k lumens, they are initial lumens. So one foot under the bub the light intensity will be 55k lumens. 2 foot from the bulb the intensity will be 1/4 of the initial intensity (13k lumens). 3 foot away it will drop to 1/9 initial intensity, 4foot will be 1/16 and so on.

If you cant lower the lights then you should raise the plants to the lights, that is if you want to efficiently use the light? And the limit for how close you can have the lights is the amount of heat at a certain distance from the lights, not the amount of light (they are only 400w after all).

Finally (and this is the most important bit), if you have one 400w bulb that produces 55k initial lumens, then you add another 400w light you do not get 100k lumens. The maximum light intensity is still going to be 55k, it will just be spread over a wider area.

Now considering the size of your grow area you are not using your lights efficiently, and you are using twice the amount of electricity you need to.

To become more efficient, and stop wasting money on electricity, I would highly recommend you run one 400w only, but bring it to within 2-3 feet of the plants. To increase your yield in that space get one 600w light in there.

I apologise in advance if I'm pissing on anyones chips :?
I just thought I'd tip you on how to increase your yield and stop wasting money on electricity.
 
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BloodShot420

Well-Known Member
partially true...

that number i got for the bulbs is pretty much ideal... it is the initial lumen output of the hortilux lamps... which i'm not sure if you are even using (i'm using the hortilux eye).

but, lumen output doesnt have anything to do with intensity... its the total amount of light the bulb puts out...

Lux ris the measure of intensity - or how much power is falling on each square meter...

the highest sunlight intensity i found was probably measured somewhere in the desert to be 140,000 lux - or 140,000 lumens/sq meter... a sq meter is 10.76 sq ft, so if you calculate that out it comes to 13,011 lumens/sq ft...

now if you slam an ideal 110,000 lumens into a closet - and you reflect them downward, they cant go anywhere or degrade - they fall on the surface you have...which is why you can calculate lumens/sq ft based on the bulb.

so if you want the intensity of his garden it would be 295,900 lux - 211% more intense than the highest sunlight intensity readings...
 
TRICKKY

TRICKKY

Well-Known Member
Lumen output has everything to do with intensity. Lux is a unit derived from lumen. 1 lux = 1 lumen per square meter.

The amount of intensity, weather we measure in lux or foot candles, is directly related to the lumen output, in that, a higher lumen output means a higher lux or foot candle.

Now if we consider that light intensity diminshes, the further away from it's source it travels, we can use a simple equation, to find the intensity of light at any given distance from the bulb.

I=L/D2 or,
Intensity=light output Divided by Distance squared

So as in my last post a source of 55000 lumens will measure 55000 lumens 1 foot away.
2 feet away is 55000/2 squared = 13750 lumens per sq foot(13750 lux)
3 feet away is 55000/3squared = 6111 lumens per sq foot(6111 lux)

Consider this, if light intensity did not diminish as it travels further from it's source, then the intensity of light from the sun, 1 foot away from the sun, would be just 140,000 lux or 140,000 lumens per sq meter. If our sun had an initial output of 140,000 lux or lumens per sq meter, we would not exist!
And finally putting to lights of equal intensity next to each other, will not double the intensity of light. It will only increase the amount of area that receives light.
To double the intensity of light you would need to put one bulb that was twice as strong.

So as I said earlier the two 400w bulbs are a waste of electricity. Especially that far away from the plants!
 
TRICKKY

TRICKKY

Well-Known Member
And just to make it really simple, put the back of your hand just under your light and look at how bright your hand is illuminated, by the intensity of light.

Now move your hand down a foot, notice that it is not so illuminated now? thats because the light intensity has diminshed.

Now put your hand as far away from your light as you can with it still under the light. Not so illuminated now?

I hope we can agree on this, it's not so important for you as your lights are close enough to the canopy and the area you are growing under can use 2 lights efficiently.

But the original poster of this thread really does need to get his plants closer to his lights. He has no need for 2 lights in an area so small and if he wants to increase his lux, lumens, foot candles then 2 lights are not the way to go about it in a space so small. Either one light closer to the plants or a more powerful light, again closer to the plants.

Peace
 
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BloodShot420

Well-Known Member
i'm not sure who can call this...

it just doesnt make sense though - if you have 1 400w bulb and you put your hand under it at whatever distance, it will feel warm, if you put another 400w bulb right next to that one, you will definately feel it get warmer on your hand, so its not exactly the same as running only 1 bulb...

I know what you are saying about the light losing intensity as it gets further from the bulb, but that does not change the lumen output of the bulb.

i think the actual value we are looking for is luminous intensity, with is based on lumens per steradian, but the fact that the lights are inside of a reflective cabinet skew all of the calculations that would be "normal"...

it may not be the most efficient way to grow - but the question was is it too much light? and i would say, no. it wont hurt or kill the plants, and in fact they will thrive.

getting into this further will be too complicated (i hate calculus) - so take it away Trickky ;-)
 
MEANGREEN69

MEANGREEN69

Well-Known Member
hey there trikky...my cab is only 4ft high,and i can get about less then a foot away from the bulb and be ok, so the intensity is there...thats why i made such a small cab to make sure the babys can get as much intensity as i can for every plant from top to bottom..thanks the the info though..peace
 
TRICKKY

TRICKKY

Well-Known Member
BloodShot420 said:
i'm not sure who can call this...
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No worries Bloodshot, it's nice to be able to debate something on here, without it becoming a trade of insults, just cos we don't agree. So thank you for your patience ;-)

Oh and one thing we both agree on, is it's definately not to much light. I have a 600w digital in a cooltube between 1-2 foot above mine and they love it! If I could keep a 1kw light cool enough, at the same distance from my plants, it would be there in an instant.

Meangrean, if you do have those plants 1 foot away from the bulb then I apologise, I saw one picture of your lights, right at the top of the cab, and assumed that was their permanent position. If they are 1 foot away, and the plants are not experiencing excessive heat, then you are indeed using them efficiently/to their maximum potential.

Thats me done anyway, I'll shut up now ;-)

Have a good Xmas both.

Peace.
 
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