Rubbermaid box, cfl lumens/heat

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bariobrothers

Active Member
i'm currently setting up a rubbermaid stealth box as described here - https://www.rollitup.org/grow-room-design-setup/109032-54-gallon-rubbermaid-cfl-box.html

after reading dozens upon dozens of cfl grows i've pretty much come to the conclusion that with cfl, the more lights the better. however, with my current grow, heat will most definitely be an issue. that being said, what do people think the magic number of lumens/sq foot is for a rubbermaid style box? that is, what is the lumen count that will produce adequate yields and sustainable temperatures.
ideally, i would like more than 5000, but that would almost definitely overheat the box. any suggestions and comments are much appreciated

i apologize if this has been asked/answered before, i searched extensively but couldn't find an answer. thanks
 
B

bariobrothers

Active Member
i could theoretically put 20+ lights into the box, for upwards of 7000 lumens/sq ft. that would inevitably overheat the box, and ruin all of my plants

so i'll ask again

what is the lumen/sq ft of a small style grow that can produce adequate yields and sustainable temperatures?
 
M

MaxEfficiency

Active Member
Did you ever arrive at a conclusion. What is the prime number of cfl wattage in one of those Rubbermaids? What kind of fans did you use?
 
tom__420

tom__420

Well-Known Member
Your lumen total is only as high as your brightest bulb. Let's say theoretically you have 5 bulbs all rated at 2,000 lumens. You only have 2,000 lumens total but a better coverage of those said lumens. You could have 10,000 bulbs all rated at 2,000 lumens but you will only have the 2,000 lumens total. Good luck

Tom :leaf:
 
beginningbotanist420

beginningbotanist420

Well-Known Member
If you have the ability to order your materials, you should look into getting a 150w e-conolight and pairing it with a DIY remote ballast and cooltube.

Light
http://www.e-conolight.com/Product/EProductDetail.asp?ProductFamilyID=7&FGNumber=E-MT6H151G [open it twice]
--> https://www.rollitup.org/view.php?pg=faq&cmd=article&id=30

Cool Tube
https://www.rollitup.org/view.php?pg=faq&cmd=article&id=565
--> pyrex bake a round, Pottery Glass, Home Garden items on eBay.com
--> http://www.directron.com/120mmfans.html

And all for about $50!

If you need to make 2, you can make them for about $75; and 3 for about $125. You could get better coverage and lumen/ft2 for the same price by doing this.

Just my $0.02 :peace:
 
smppro

smppro

Well-Known Member
tom__420 said:
Your lumen total is only as high as your brightest bulb. Let's say theoretically you have 5 bulbs all rated at 2,000 lumens. You only have 2,000 lumens total but a better coverage of those said lumens. You could have 10,000 bulbs all rated at 2,000 lumens but you will only have the 2,000 lumens total. Good luck

Tom :leaf:
Click to expand...
So then by this you are saying lumens doesnt matter right?
 
bnoc450

bnoc450

Well-Known Member
smppro said:
So then by this you are saying lumens doesnt matter right?
Click to expand...
what he is saying is that 1 2000 lumen bulb is equivalent to 10 2000lumen bulbs so according to him more bulbs dosent increase lumes so just use 1 2000 lumen bulb instead of 10 and u will get the same results
 
Tanuvan

Tanuvan

Well-Known Member
tom__420 said:
Your lumen total is only as high as your brightest bulb. Let's say theoretically you have 5 bulbs all rated at 2,000 lumens. You only have 2,000 lumens total but a better coverage of those said lumens. You could have 10,000 bulbs all rated at 2,000 lumens but you will only have the 2,000 lumens total. Good luck

Tom :leaf:
Click to expand...

Sorry man, but this is just not correct at all. Lumens do add...it is easily explained with physics. What does not add is intensity. Lumens have to do with the number of photons hitting a specific area. The more bulbs you add...the more photons are hitting that area. You can also use a light meter if you don't want to calculate the equations.

It really gets technical as the idea of lumen in and of itself is subjective because it has to do with the sensitivity of the human eye...i.e green light appears brighter or more luminous to humans than say blue. In short, lumens do actually add.

As an aside, the lumens from multiple bulbs do not add linearly because the photons emitted do not start at the same source. You can refer to trigonometry for that as well. This is because the spot directly beneath bulb (A) will receive X number of photons. Bulb (B) adjacent to it will still emit photons beneath bulb A, but due to the inverse square law and the angle which will be greater than 90 degrees or 0 degrees depending on how the bulb is mounted it will produce fewer actual photons underneath bulb (A) than those emitted at the origin (Bulb A). In order to double the lumens, BOTH bulbs would have to occupy the same physical place in space...which is impossible...and that is the reason why intensity does not change with more bulbs. The overall lumens per given square foot will add in an enclosed area. But under a specific point under any one bulb, they do not add linearly, but they DO add.

You can have the same number of lumens as an HPS with CFL, but not the same intensity. As to the OP, you want between 4-5K lumens per sq ft ...otherwise your yields will be less than desireable.


If you really really care for the experiments ... see this link

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

And this

https://www.rollitup.org/indoor-growing/83378-16k-lumens-hps-vs-cfl.html
 
smppro

smppro

Well-Known Member
bnoc450 said:
what he is saying is that 1 2000 lumen bulb is equivalent to 10 2000lumen bulbs so according to him more bulbs dosent increase lumes so just use 1 2000 lumen bulb instead of 10 and u will get the same results
Click to expand...
wait so you are saying 1 42w cfl will produce the same as 4-42w cfls because the lumens match? If you add more bulbs you WILL get more light to the plants and yield more plain and simple, so if the lumens dont add up then lumens dont matter because the plants are getting more light
 
bnoc450

bnoc450

Well-Known Member
smppro said:
wait so you are saying 1 42w cfl will produce the same as 4-42w cfls because the lumens match? If you add more bulbs you WILL get more light to the plants and yield more plain and simple, so if the lumens dont add up then lumens dont matter because the plants are getting more light
Click to expand...
that is what tom_420 is saying...not me
 
O

overmind1632

Active Member
Tanuvan said:
Sorry man, but this is just not correct at all. Lumens do add...it is easily explained with physics. What does not add is intensity. Lumens have to do with the number of photons hitting a specific area. The more bulbs you add...the more photons are hitting that area. You can also use a light meter if you don't want to calculate the equations.

It really gets technical as the idea of lumen in and of itself is subjective because it has to do with the sensitivity of the human eye...i.e green light appears brighter or more luminous to humans than say blue. In short, lumens do actually add.

As an aside, the lumens from multiple bulbs do not add linearly because the photons emitted do not start at the same source. You can refer to trigonometry for that as well. This is because the spot directly beneath bulb (A) will receive X number of photons. Bulb (B) adjacent to it will still emit photons beneath bulb A, but due to the inverse square law and the angle which will be greater than 90 degrees or 0 degrees depending on how the bulb is mounted it will produce fewer actual photons underneath bulb (A) than those emitted at the origin (Bulb A). In order to double the lumens, BOTH bulbs would have to occupy the same physical place in space...which is impossible...and that is the reason why intensity does not change with more bulbs. The overall lumens per given square foot will add in an enclosed area. But under a specific point under any one bulb, they do not add linearly, but they DO add.

You can have the same number of lumens as an HPS with CFL, but not the same intensity. As to the OP, you want between 4-5K lumens per sq ft ...otherwise your yields will be less than desireable.


If you really really care for the experiments ... see this link

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

And this

https://www.rollitup.org/indoor-growing/83378-16k-lumens-hps-vs-cfl.html
Click to expand...
Exactly, thank god you posted this or I was gonna have to correct tom
 
worm5376

worm5376

Well-Known Member
this is def not true . 1 bulb or 10 you still get 2,000 lumens but you need more coverage!!! so in a tote box i would put 5 yellow/red bulbs and 3-4 blue bulbs to cover the whole spectrum. Not that hard so try and keep it simple.. Just a thought.
 
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