L.E.D. grow lights?

ledgrow said:

Either you people don't know how to read, or your reading comprehension is so low you just cant grasp anything I said and instead continue repeating the same shit mindlessly instead of being able to respond to the comments.

Let me try again, maybe somebody somewhere will understand.

LUMENS DO NOT MATTER WHEN MEASURING GROW LIGHTS

LUMENS DO NOT MATTER WHEN MEASURING GROW LIGHTS

LUMENS DO NOT MATTER WHEN MEASURING GROW LIGHTS

LUMENS DO NOT MATTER WHEN MEASURING GROW LIGHTS

If you dont believe me then fucking GOOGLE IT. You are using a measurement that is WEIGHTED for the yellow-spectrum which happens to be the least efficient for plants. Lumens mean NOTHING to plants.

This site does a very good job explaining it: Light and Plants

Second, you guys look at this picture and nobody sees anything wrong?

The following are reasons why this picture is complete crap:

1. You are pointing 2 lights directly into each other's reflectors and then taking a brightness measurement from the side.... ?!?!
2. One light bulb is covering the light output from the other
3. You are trying to take an accurate measurement from 50 millimeters away from the bulb.

Here is a diagram of the correct way to measure lumen output:
Common Light Measurement Terms

Try measuring it properly by pointing both lights directly at the sensor from 1 foot away, and then come back with your "empirical evidence"

This forum is proof of what can happen when people who dont know how to follow the scientific method try and do experiments.

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ledgrow said:

Look man, I don't know who you are or where you get your information (its certainly not based on science), but I just couldn't take the complete inaccuracy of your post so I decided to make an account so I could respond.



You need to calm down man. I don't know if you just had a bad experience with led growing or what but saying "absolute crap" and "bullshit" just proves you dont know what your talking about. Furthermore, it should be illegal for you to post all that completely bogus information and pretend like its truth.

Again, you have no clue what you're talking about. There is a very good reason why led grow lights dont have a lumens rating - its because lumens is a measurement based around YELLOW-WAVELENGTH light. Did you even read the FAQ on that superled page? Or maybe try wikipedia:
Lumen (unit) - Wikipedia, the free encyclopedia

You cant measure an led grow light in lumens because led grow lights are tailored to the wavelengths plants are most sensitive to. An led grow light could have a MUCH LOWER lumens rating than another light but grow infinitely BETTER. Obviously LED lights will have lower "lumen" ratings, but using lumens as a measurement for growing purposes is completely worthless!

Look at this chart of plant Chlorophyll absorption:
Image:Chlorophyll ab spectra.png - Wikipedia, the free encyclopedia

Now look at the graph of the lumen unit measurement:
Luminous flux - Wikipedia, the free encyclopedia

"The luminous flux accounts for the sensitivity of the eye by weighting the power at each wavelength with the luminosity function, which represents the eye's response to different wavelengths." In other words, lumens are good in measuring light for humans but completely irrelevant in measuring light for plants.
Make any sense?

uhhh, where in gods name did you get such a patently WRONG idea and become so certain it was true?
I hate to have to explain such a common-sense concept... but adding two 15 lumen lights together pointed in the same direction IS roughly equivalent to a 30 lumen light.

Eh? What in the hell are you talking about man? This is completely wrong.
Try staring at a flashlight for a few seconds. Now get 5 of the same flashlights, tie them real close together and stare into them. Do your eyes hurt more? Well they shouldnt! Light output shouldn't be any different from one flashlight! Right?!?

Its a simple concept. Light = energy. More sources of light = more energy.

If you have ever measured light you would know this is just simply not true. Adding more leds WILL increase the overall lumen output. (Ignoring the fact that using lumens to measure growlights is just stupid to begin with.)

Ahh yes the moment of truth. Anybody who thinks they will grow dope is a FOOL, you say? You should really watch what you say at the cost of looking very very stupid.

The following pictures are of the Lowryder2 strand grown from seeds using an ebb & flow system w/ canna nutrients on a 16hr light cycle all the way through. This was done using only the LightBlaze 400 which happens to be the light you are bashing in this thread.

Shes a baby->

Getting bigger, looking healthy->

Yep, 100% LED grown. VERY happy with the lightblaze 400 from LED Grow Lights - Plant Grow Lights ->

And heres a closeup ->

So what were you saying there about being a fool?

Stop acting like you are so sure of yourself. I had no troubles growing my MJ plant and people who see it are so thrilled they have been convinced to buy an LED unit themselves. There are certainly a lot of crappy led grow lights which are scams, but that doesn't mean the entire technology is flawed!

NASA is successfully using leds to grow plants in space (try googling it), maybe you could enlighten them with what you know and convince them they are wrong.

Unless you want to come back and tell me my pictures are photoshopped, i suggest you stop touting your incorrect assumptions.


You can talk shit on LEDs all you want, but my results are not isolated. There are others having just as much success as me and eventually you are going to look more stupid than you do already. peace.

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endive said:

Wow, so much HID vs LED aminosity... and I thought herb mellows the soul.

Just because you prefer one method, doesn't mean you need to bash anyone and everyone who believe differently. No doubt, MH/HPS grows can consistantly produce some amazing returns. However, I've seen recent LED grows that are nearing the 1g/watt harvest ratio, in both smaller stealth grows (< 1.5 m2) as well as some respectably larger ones (> 18m2).

Grow with what you know, illuminate with what light source you prefer. Be nice to others, plain and simple.

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passtheblunt said:

HAHA i just have to laugh at this...

im sorry Al. B fuct

but you just got royally pawned by ledgrow

aw that made my day reading that lol

just loved the way he took your arguement apart bit by bit top notch ledgrow

sorry, had to be said

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sammons said:

I won't quote anyone because this thread is just too jam packed full of rubbish I'd be here all day. LedGrow has said some pretty convincing counter arguments to the dribble that has been said and there are still stubborn and under educated people trying to argue their misinformed point of view. If you would like to get up to speed with the whole LED thing please read below:

First a little History:
I am a Mechatronic Engineer and have been serious about researching LEDs for growing for 4 years. When I started my research, LEDs were not up to scratch to effectively grow plants! The theory was there but not the production. In the year 2000 SolarOasis engineers developed and manufactured the world's first commercial LED plant grow light, it was insanely expensive then and it still is now and it is still ineffective. Around 2005, Hype about High Power LEDs started to get people interesting in the potential of LEDs. Then people started to advertise "LED Panels" as so called "LED Grow Lights" that still used 5mm LEDs and were also severely under powered. But unlike The Grow Bars from Solar Oasis they only used 470nm Blue and 625nm red LEDs which are the cheap, common LEDs. The forums lit up with people asking about grow lights and there were many making their own. The realisation of the Procyon 100 light was the first commercial example that I was aware of that used high power LEDs. Unfortunately it doesn't work as it was hoped either. It contains only Cree Red and Blue LEDs which are not actually aligned to the Photosynthetic response of both Chlorophyll A and B as much as they try to tell you. Thus, is not only inefficient, but is missing other colours that we now know are also important (UV and FR. Other manufacturers produced similar lights like the famous UFO light that has been so heavily copied in china. More powerful lights began to emerge from china but still restricted to the Red/Blue mostly due to cost, but also due to demand to get any old LED grow light into the market.

The LED Lighting market is developing at an extremely fast pace and research and development is increasing the efficiencies at an exponential rate, and the cost of LEDs are coming down dramatically. As of January 2009 there has been a breakthrough that promised to be able to reduce the production costs of LED dies by 90%. As that sort of technology filters through to the manufacturers and LEDs become used as the predominant lighting source, the retail price will drop even further. Lights are developing and since early 2008 TriBand and QuadBand LED lights have begun to emerge as the manufacturers have realised that the RED/BLUE lights are failing to produce results in budding/flowering. These new lights can have UV (395nm), Royal Blue (455nm), Orange Red (630nm), Deep Red (660nm), and FR (730nm).

There is no point sitting around crying that your UFO that you bought of Craig's list isn't working. Don't come to forums to whine that LEDs are no good and people should stick with HPS. If you had done your research you would know that its not the LED technology that are failing you, it is the mis-use of the technology and mis-representation of what LEDs are capable of. With such a cut throat market, and a mass of stupid people, of course people are going to cash in on the LED hype. But the Fact remains, LEDs will be the future of indoor growing whether you like it or not. Companies are using the revenues from sales of crappy LED Lights to fund the research that is required to produce better lights.

As for penetration, light is Light, the difference is the frequency. A possible explanation why light from a MH or HPS would "Penetrate" the plant canopy better is because plants do not absorb green/yellow/orange light very well. The light either passes through or is reflected, giving the lights chance to bounce around and get further down to lower leaves. These frequencies are not absorbed by plants, so the perceived increase of light penetration of a HPS does not mean that your plant is getting more usable light.

Next point I would like to make. LEDs are a different light source. It’s not like removing a Metal Halide and putting in a HPS. They don't emit light in the upper infra red region (radiant heat). This is both good and bad. GOOD because it will be the end of frying your leaves and buds and end to wasted energy and end to noisy, expensive extraction fans and carbon filters and greatly reduced heat signature! But BAD because during winter your indoor grow may end up being too cold. You may need to think about not only ventilation but heating as well. But that is not the end of it. If you have tried growing with 600W or 1000W HPS you end up having to ventilate your grow area in order to cool everything down due to the enormous amount of heat generated by the lighting. If you want to add any CO2 it’s much like an open fire, 90% will go straight up the ventilation shaft. The use LEDs makes it possible to seal off the grow space and introduce CO2 without it all blowing away.

The rated lifetime of LEDs is often stated as 50,000 hrs, it is incorrect to assume that after 50,000 hrs the light is no longer usable. The figure means that in 50,000hrs the light output will be 70% of its original brightness. And in 50,000hrs after that is will be 70% as bright as it was after the first 50,000 hrs, so in theory will just get duller and never actually die. (As long as the power supply can keep going that long)

So now we have a light source that uses half the energy to produce the same results, doesn't burn our plants, and reduces suspicious electricity bills. LEDs make it possible to eliminate smells and open the way for increased production through CO2 supplements. LEDs have an instant on (no warm up) and no cycle times we have to worry about. No more dead timers from the inductive load of inductive ballasts killing the relays and won't need replacing for a long time.

Unfortunately LEDs are not cheap! It is the efficiencies and features I mentioned above that make LEDs so promising. If you are trying to grow on the cheap, LEDs may not be for you. However, you can get a single 600w LED 5 Band LED light for less than US$900 posted to your door. If you can make that back in less than 6 months, the next 7-10 years is all profit and much more stealthy.

Just don't go around saying they don't work as well as a 600w HPS until you have tried a grow with 600w LED using UV, BLUE, RED, Far RED LEDs. Please Please Please don't go around saying, "I have tried LEDs and they suck" when all you have done is stick your plants under a 10w LED panel off eBay!!!
Regards
Phil

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nickfury510 said:

yeah.leds suck...i tried em and got rid of them about half way through veg.....pllus ..that set up looks complrtley inneficient...

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IAm5toned said:

I have a clue what im talking about...
credentials:
6 certifications in major lighting systems, from all the big commercial manufacturers.
4 years engineering school
4 years electrical trade school, and currently working on my masters.
i have designed and installed some of the most advanced lighting systems sold.
working on my 18th year in the industry.



LED's are crap for growing...... they will work, but with nowhere near the efficieny of HID lighting. its that simple.
i can 12/12 from seed under HID and have tighter, frostier, heavier buds than the same strain/grow duplicated under LEDs
and for the record, lumens have shit to do with growing anything.
a lumen is a unit of measurement for visible light, not actual light output.
if you measure the intensity of a lamp (any lamp) with the intention of comparing the results for growing, you need to speak in terms of Photosynthetic Action Ratings (PAR)
ex- a 1000w MV lamp will not perform anywhere near as well as a 250w HPS or MH... why? because the MH and HPS have a much higher PAR rating than MV...
do some research instead of buying into technology... technology is nice, but you forget one key thing about it:
technology is sold by people that are in business to make money, not help you with your grow.
if they think they have a valid selling point, (as LED manufacturers do) they will tell you exactly what you want to hear to get your money.
the people on this site have no vested interest in making money off your grows... some of them are pros that have been at it for decades. im not telling you what to do, but you might want to listen more and talk less, so you that learn something usefull, instead of just blindly following false promises made by people that are out to make money.
at this point in time, 600w HID lamps will produce the best quality light for the wattage consumed. whether you use MH, CMH, or HPS is a matter of preference.
see, you just learned something valuable from an industry expert..........

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