CFL vs HPS penetration

smoothopyro

Active Member
https://www.gardenscure.com/420/lighting/79048-cfl-penetration-trimming-theory.html

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

The big question: assuming no energy limit, if I have 10000 lumens of CFL, WILL IT PENETRATE LESS THAN 10000 lumens of HPS? In other words, lumen for lumen, does HPS actually penetrate deeper than CFL, or is HID more just more efficient at generating this penetration (more penetration per watt)?

it doesn't seem like it would, especially if the CFL light was coming from a uniform source (like several CFLs spaced very close).

Prove this, please. I don't want any "well, I grw under HPS and then CFL and xxxx happenned". THat's all well and good, and I'm aware of the differences between the two in terms of efficiency, spectrum, heat, etc. I want a conclusive answer, backed with empircal data or sound logic, to this often-asked question.
 

nickfury510

Well-Known Member
as far as i understand it just as watts is watts. lumen is lumen. if one could create a 150w cfl that produced 16,000 lumens and compared it to 150w hps in the same color spectrum they would produce the same. it comes down to lumen per watt as far as efficiency.
 

zoink29

Well-Known Member
yea lumens are a measure of light intensity...more light more penetration.... hope thats logical enough
 

smoothopyro

Active Member
THat's what I was thinking...I couldn't think of any reason they would be different. So a 276W CFL lightbox (12 CFLs in 1 square foot) would be just as good (or better than) a 150W HPS?
 

zoink29

Well-Known Member
during veg the plants like blue spectrum (CFL) flowering plants like red spectrum (HPS).. but you can go through the entire grow with either... 12cfl's in 1sq.ft should do u just fine
 

smoothopyro

Active Member
the actual flowering area would be more like 2 square feet, really. The lights would be secured on a moving platform, though, approx 16"x12", with 8 horizontal CFLs and 4 vertical ones on the corners.

Aw hell, I even took the time to make a sketchup of my design so I could visualize the space better, I'd appreciate it if you checked it out. It's gonna be a DWC ScrOG in a 15"x21"x36" stealth cabinet.

ScroG Stealth Box
 

GrowGreenGreen

Well-Known Member
It's all about direction. All bulbs emit their photons generally as a point source. If you use properly matched, efficient reflectors correctly, you will direct all of the photons in the right direction, and both bulb types will be about as effective at delivering photons to the area intended, spectral qualities of the photons aside.

But 10000 lumens from a single HPS needs to be distributed much differently than the 10000 lumens from a group of separate bulbs. In this way, the CFLs, placed throughout the canopy, spread their photon flux more evenly. You can thusly illuminate your plants how you like by movng the bulbs around for optimum coverage. Multiple HPS bulbs can be used this way as well, however the temperature differences are obvious, and their PAR-Watt efficiency is severely lacking for this reason.
 

Steadmanclan

Well-Known Member
on a tiny grow like that cfl will suffice. at low watts with small plants you won't notice a huge difference if you keep using cfl's throughout instead of hps. it's only when you want to grow big plants with big fat buds that you need to think about the superior growing power and penetration of hps. cfl's can't compare with anything 400 watts and over. it's not even close.
 

Brick Top

New Member
The single most important thing that it appears that some people do not know is that HID lighting produces more grams per watt than CFL’s do.

HID lighting penetrates deeper into plants and through foliage better than CFL’s do, that is a proven fact.

Just stop and think about it a moment. Where do you position CFL lights to get the most out of them? Close to the tops of your plants. What happens if you have CFL lights to high? Plants will stretch due to low light conditions.

Ok .. think about that a moment and what do you come up with? CFL’s have to be close to plants to be at their peak efficiency, right? That is due to how CFL lighting disperses quickly and how it does not penetrate as deeply as HID lighting.

Also it is more than obvious that positioning CFL’s just a couple inches to high will create low light conditions for your plants, right? Again that is due to how CFL lighting disperses quickly and how it does not penetrate as deeply as HID lighting.

So what happens to the middle and the lower portions of plants as they grow and CFL lights have to be raised? Each time you raise CFL lights that creates another inch or two or three lower down the plants that now is out of the range of adequate CFL light penetration. They receive less and less light as the lights are raised and they produce smaller buds and lighter fluffier buds and that is easily seen when you figure out the amount of watts per grams produced.

I just do not and never will understand the CFL craze that many people here seem to have fallen for. I have grown for decades, close to four of them, and I have been a member of numerous grow sites and I have never seen or known people as in love with CFL lighting as I see here.

CFL lighting has a place in growing. CFL’s are useful in a computer case grow or a small cabinet grow or to root clones and to keep mother plants alive but for general growing CFL’s do not do the job like HID lighting will do.
 

Mcgician

Well-Known Member
as far as i understand it just as watts is watts. lumen is lumen. if one could create a 150w cfl that produced 16,000 lumens and compared it to 150w hps in the same color spectrum they would produce the same. it comes down to lumen per watt as far as efficiency.
Close, but not exactly. Brightness and luminosity are two completely different things. A 400 MH is brighter than a 400W HPS, but the HPS is more luminous than the MH.

The reason for this is the difference is absolute magnitude, and the spectrum of light they emit. Astronomy geeks will recognize it as the formula,

b= L/A

or more in depth as,

[edit] Computing between brightness and luminosity

Imagine a point source of light of luminosity L that radiates equally in all directions. A hollow sphere centered on the point would have its entire interior surface illuminated. As the radius increases, the surface area will also increase, and the constant luminosity has more surface area to illuminate, leading to a decrease in observed brightness.
where
A is the area of the illuminated surface. For stars and other point sources of light, A = 4πr2 so
 

GrowGreenGreen

Well-Known Member
So what happens to the middle and the lower portions of plants as they grow and CFL lights have to be raised? Each time you raise CFL lights that creates another inch or two or three lower down the plants that now is out of the range of adequate CFL light penetration. They receive less and less light as the lights are raised and they produce smaller buds and lighter fluffier buds and that is easily seen when you figure out the amount of watts per grams produced.

That's why we like to place CFLs down into the canopy, something trivial to do with a CFL, but not with any ol' HPS. By enveloping the plants in uniform luminance, we achieve excellent vegging results. Then we change the spectrum and photoperiod and continue. It takes a little longer with off-the-Home-Depot-shelf CFLs than MH, of course.

I just do not and never will understand the CFL craze that many people here seem to have fallen for. I have grown for decades, close to four of them, and I have been a member of numerous grow sites and I have never seen or known people as in love with CFL lighting as I see here.
Haven't you ever wondered if you could reduce your carbon footprint? Or save money on power? Or run your fans and A/C less? Or avoid skin-melting dangers? All while improving internodal length?

Yeah. Us too. >>>>> C. F. L. :leaf:
 

B.C Chef

Active Member
Close, but not exactly. Brightness and luminosity are two completely different things. A 400 MH is brighter than a 400W HPS, but the HPS is more luminous than the MH. The reason for this is the difference is absolute magnitude, and the spectrum of light they emit. Astronomy geeks will recognize it as the formula, b= L/A or more in depth as, [edit] Computing between brightness and luminosity Imagine a point source of light of luminosity L that radiates equally in all directions. A hollow sphere centered on the point would have its entire interior surface illuminated. As the radius increases, the surface area will also increase, and the constant luminosity has more surface area to illuminate, leading to a decrease in observed brightness. where A is the area of the illuminated surface. For stars and other point sources of light, A = 4πr2 so
Ya.......I agree the HPS will definitely reach father. I am on my first grow and can tell you even switching to a 150w HPS light (sunsystem 150w hps all enclosed) made a huge difference. I actually used a light meter and my 42w cfls put out good light but only for a 3-4 inches where my HPS is good for like almost 12 inches to sustain the same light level. I did the math and CFL's seemed better but in reality the penetration is very important and makes a huge difference in growth.
 

Brick Top

New Member
That's why we like to place CFLs down into the canopy, something trivial to do with a CFL, but not with any ol' HPS. By enveloping the plants in uniform luminance, we achieve excellent vegging results. Then we change the spectrum and photoperiod and continue. It takes a little longer with off-the-Home-Depot-shelf CFLs than MH, of course.

That is right, about how people who use CFL’s need to position them at different levels but that is only due to their lack of light penetration so you validated what I wrote.

The major disadvantages of compact fluorescent light bulbs are their inefficiency and poor light penetration.

A bank of several compact fluorescent light bulbs can use as much energy as one HID bulb, but will not produce anywhere near as much usable light for indoor growing.

Picking CFL lighting is picking an option that has inherent flaws that have to be made up for through redundancy, the use of numerous lights to attempt to do the same job that one single HID light would do.

I look at pictures of people setup and see CFL’s positioned at several levels and the light cords hanging all over and extension cords running all over and then I look at how my setup looks and I see one light and one cord.

I do not need multiple outlets to plug into. I do not need power-strips to plug into. I do not need Y-sockets to be able to get enough light to plants on all levels. I do not need to walk over and through and work between numerous light cords and extension cords.

It is lunacy to intentionally pick a poor option for something and then attempt to make up for it by just using more of the same poor option when there is a single proven better option to pick.



Haven't you ever wondered if you could reduce your carbon footprint? Or save money on power? Or run your fans and A/C less? Or avoid skin-melting dangers? All while improving internodal length?

Carbon footprint? Please do not attempt to use the manmade global warming myth as a valid reason to use CFL lighting. That is beyond just being absurd. Also as I said above a bank of several compact fluorescent light bulbs can use as much energy as one HID bulb, but will not produce anywhere near as much usable light for indoor growing so that being the case if someone actually believes in the myth of manmade global warming what is gained by using multiple lower wattage lights that when totaled can use as much energy as a single HID light?

Do you know how many lights of the various different grow lights it takes to produce an equal amount of light as a 400-watt HID light produces? If not see the attached image.

To equal the light output of a single 400-watt HID light you need 5.3 125-watt CFL’s. That totals 662.5 watts used to achieve the same amount of light a single 400-watt HID light will produce. How does that reduce your "carbon footprint?"

People talk about heat problems and HID lights are often said to generate more heat than CFLs. That's not really true...it's just that they are more efficient at producing light, and there's a smaller surface area on the bulb itself for the resulting heat to dissipate. That means more ventilation. But the higher amount of lumens per watt means you use less power and get greater light penetration through your canopy. Again, less power used and there is your precious "carbon footprint" being reduced.

You mentioned saving money on power but the way I look at it I am saving a lot more money by growing my own ‘herb’ than by buying it so I have already saved way more money than I would otherwise have spent so I am already ahead of the game. Then when you factor in the grams per watts and how HID lighting is proven to produce more grams per watt again money is saved because there is a higher yield.

I would never attempt to claim that someone cannot burn themselves if they touch a HID bulb but then I have grow for decades, close to four of them, and I have never once burned myself so I do not consider it to be a real danger and more just something that some people attempt to use for one more reason to justify picking a poor option for their choice of lighting.

As for internodal length, well I have had plants growing indoors at the same time that I have had plants growing outdoors in the full sun, without any shade at all, and the difference between internodal length was absolutely minimal, there was an amount so slight that it was immeasurable with a common tape measure, so I find it impossible to believe that CFL’s will outperform HID lighting AND also the sun. To believe CFL’s can outperform HID lighting AND also the sun someone would have to be naïve at the very best.
 

Mcgician

Well-Known Member
^Damn, and I thought I was a nerd. lol. Without even touching on the subject of lumens per watt, did anyone consider how many BTU's it takes to actually MAKE the bulbs themselves vs. one 400W HPS or MH? That's really the question. They may be a nice option compared to incandescents when it comes to light output per watt, but nobody ever thinks about how much energy went into the CREATION of the bulbs in the first place. The similarity between this subject and the one about photovoltaics is striking.
 

smoothopyro

Active Member
Excuse me for interjecting into my own thread...so much discussion here, and it all seems like valid advice.

could I get away with using a 150W HPS? I want to keep the distance between the light and the plant not more than 6", even when the light is fully raised, and I will only be running a passive intake and a 120mm case fan for exhaust. I don't know if I even have room for a reflector for an HPS. Size constraints are forcing CFL, but if I could use HPS with better results for little size difference I would switch the setup.

CFLs also were a cost consideration, but after looking at costs for 12 CFLs, fixtures, wiring, and still being unsure about the yield quality, and ultimately, potency, I would feel safer, and it would be cheaper, using a gerry-rigged HPS than betting my odds at wiring 12 individual sockets correctly.

I chose CFLs, despite my uncertainty, because of space and cost and heat issues. If you can ease my mind on those issues, then I might make the switch.

Edit: I will also have 2 small case fans circulating air through the cabinet, either way. All fans will be run 24 hours.
 

Mcgician

Well-Known Member
Excuse me for interjecting into my own thread...
LOL. Here's the deal dude. If you want any kind of decent sized buds coming off your plant(s) (you still haven't told us how many you're growing btw), I don't recommend anything less than a 250, but preferably 400W. The heat coming off a 400 is not that bad, and if you can dedicate that light to between 1-4 plants, you're going to end up happy. If you choose to go with less, let us know how it goes. Good luck.
 

smoothopyro

Active Member
LOL. Here's the deal dude. If you want any kind of decent sized buds coming off your plant(s) (you still haven't told us how many you're growing btw), I don't recommend anything less than a 250, but preferably 400W. The heat coming off a 400 is not that bad, and if you can dedicate that light to between 1-4 plants, you're going to end up happy. If you choose to go with less, let us know how it goes. Good luck.
I would feel most comfortable if you could give me a figure, in inches, that an HPS of that size would need to be from the canopy (we are talking scrog here). I would rather give the plants too much light, barring burning them, than have to keep the light far away. Space and heat are my primary concerns Also, I want to be able do a short veg to establish my clones, and I was wondering if I can do this successfully with the HPS?
 

psg1

Active Member
To the OP: be wary of statements by those using phrases like, "the only way to" or "if you want any kind of decent" etc etc. There are more than a few ways of doing things, and they are not mutually exclusive by any means.
 
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