1w, 2w, and 3w LED penetration discussion

[GeorgeWBush]

So, I hear lots of different things about these led's. 1w are supposedly the most efficient, but don't penetrate more than a couple inches. People say 2 and 3w penetrate pretty nicely and I'm seeing some great results from people.

Have any of you hit 1GPW with the 1w led?

I have read a few threads from people getting 1GPW+ from the 3w led.

How about the 2w? Any success stories?

If anyone can chime in from experience what kind of penetration they are getting from their LED I'd love to read about it.

Or if you just want to add some theory to the discussion I'm all ears. Thanks.

-Dubya

 

[WasntMe]

it also depends on the degree spread of the lens 60, 90, etc.... if you look around you will see many LED grows hitting the 1.4+ GPW


P.S. you grandfather was traitor that didn't deserve a pardon ... he deserved even more jail time for war crimes then you do.

 

[GeorgeWBush]

One thing I find interesting on all led grows I've seen is that they all have a flat horizontal canopy.

My thought is that if you were to spread the canopy in a scrog along the sides of the walls, you could double your surface area. Reason would tell me this will increase production.

Interesting no one has tried this.

 

[WasntMe]

One thing I find interesting on all led grows I've seen is that they all have a flat horizontal canopy.

My thought is that if you were to spread the canopy in a scrog along the sides of the walls, you could double your surface area. Reason would tell me this will increase production.

Interesting no one has tried this.

due to the lens angles that are typically used and the throw distance of effective light from the LEDs.... the light distribution dictates that a flat canopy directly under the panel is the most effective formation.

unlike a HID bulb's 360 throw that can be hung vertical to take advantage of side spacing.

HGL does make a a Vertical format LED panel array but I haven't seen a test grow with that one to see it's effectiveness.

 

[sm0k4]

The tight pattern of most commercial lamps with less than 100 degree lenses only allows for growing under the lamp area. The lenses keep the light focused in a more tight beam so you do not get the side lighting.

1W emitters are most efficient lumens per watt, but they need to be close to the tops and have little penetration.

3W are less efficient but seem to work just fine. I think I will use some 3W emitters for a bigger light I am designing to go in a 4' x 2.5' cab.

I think its more the grower than the equipment when it comes to LED. I already made 3 modifications to my custom LED array. So far so good. I think I got the stretch under control. As long as you provide the photons the plant needs, should all be gravy baby.

 

[Kcar]

This one looks pretty good. Good price too...

http://www.357magled.com/

 

[GeorgeWBush]

Can anyone give some numbers when it comes to amount of penetration with different watt led's?

Also, if you are successful with LED's and have a good GPW please show it off and show us how you do it! I'm here to learn.

wasntme and smok4- Thanks for your input. That makes sense. The thing is for me though, that I can see that light is hitting the walls in a typical grow box, so why not utilize that light, even if it is not as strong. Seems that whatever foliage is put there should flower. Why waste the space? I dunno, just a thought. If anyone has tried it please chime in.

Smok4- where can someone get led's to make a diy light? I know ideally you are looking for particular spectrum.

Also, there is a lot variation as far as what people say is best as far as spectrum. Some make a triband with orange, some with white, some have multiple spectrums including infrared. Seems that no one actually knows for sure what is ideal.

 

[sm0k4]

Can anyone give some numbers when it comes to amount of penetration with different watt led's?

Also, if you are successful with LED's and have a good GPW please show it off and show us how you do it! I'm here to learn.

wasntme and smok4- Thanks for your input. That makes sense. The thing is for me though, that I can see that light is hitting the walls in a typical grow box, so why not utilize that light, even if it is not as strong. Seems that whatever foliage is put there should flower. Why waste the space? I dunno, just a thought. If anyone has tried it please chime in.

Smok4- where can someone get led's to make a diy light? I know ideally you are looking for particular spectrum.

Also, there is a lot variation as far as what people say is best as far as spectrum. Some make a triband with orange, some with white, some have multiple spectrums including infrared. Seems that no one actually knows for sure what is ideal.

I wish I was more experience with results, but my seedlings are only 1 week old under my custom LED array. This is my 1st grow with LED, so I started out in a PC case to get the bugs worked out before moving up to my 4' x 2.5' cab design.

Some things I read/observed from others:

The LED light is most efficiently used when it can reflect off the walls. I set my light so that it covers the whole area and reflects off the walls. I have a 12" x 5" light profile in a 14" x 6" chamber. This is the ideal situation for LEDs. Enclosed spaces for maximum light density and the reflection will help. My light is .5" away from my side walls and they reflect back real nice and bright. I used a silver paint with metallic flakes in it that diffuses the light pretty well. Some complained about the narrow beam with LED emitters and I heard diffused light sources are better, so I hope this helps a bit.

Between 1W and 3W emitters the only difference is penetration after efficiency. Do you want 3 foot or taller plants? If so use 3 or 5W emitters since they are more intense. Or go with side lighting. But then be ready to compensate for the heat if going to 3W or 5W. I think 1W emitters go effectively up to 2 feet, then its pretty much downhill. So 3 foot max. is what I would grow with 1W emitters.

Nutrient and water uptake is different, go slow and feel it out. I decided to go coco coir since LEDs aren't as intense. I figured they would be less susceptible to over-watering and root rot this way. Gotta stay on top of pH and runoff more though.

I ordered my first batch of supplies from customhydronutrients.com. KNNA has been testing and researching LEDs for a long time now and has selected those on that site as being the best bang for the buck. The same parts at normal distributors will cost you more if you get less than 200 of them at a time. You can use whatever LEDs you want though. Just read and compare datasheets. Osram Golden Dragon plus is a good one to go by. Their 1W emitters beat some 3W emitter's lumen output because they are way more efficient.

It took me about a month of steady reading and researching before I felt comfortable enough to make sense of lighting, the LED datasheets, and driver topologies. For people to just dismiss LED is funny to me now because they have no clue what they are talking about. LED is viable, just have to use them right and spend some money on the good ones IMO. Otherwise you are throwing out weak light and a lot of wasted heat. I hope my results improve with every LED design I do. I won't quit modifying until I stop seeing improvements.

Buck topology is about the easiest one if you are looking to DIY your driver circuit as well. CAT4101 is what I use. Cheaper cost per watt since I would need a lot of power from commercial drivers which will cost over $200. My driver component costs are around $150 for my big light. Decent savings if you have the means.

KNNA has a lot more in depth info on the emitters and light in general. This is just the cliffs notes version with lots missing I'm sure.

 

[GeorgeWBush]

Smok4- That's interesting, why is is most efficient when it can reflect off the walls? I always thought that diminishes lumens. Do you have any pics of your light? Sounds cool.

Anyone have data on the 2w bulbs? I managed to pick up a ufo with 45 2w, red, blue, and white. They said a 2' distance is ideal and will create a 3'x3' space. Not sure what I can expect as far as penetration. Looks like a scrog is the way to go.

Brand new to led. Funny, there's still not a ton of info it seems, but I think the potential is so great that one day this will be the preferred method once it gets dialed in. People pass this off as a fad. Haha give it a couple years. There's too many growing and security benefits to just dismiss.

 

[sm0k4]

Smok4- That's interesting, why is is most efficient when it can reflect off the walls? I always thought that diminishes lumens. Do you have any pics of your light? Sounds cool.

Anyone have data on the 2w bulbs? I managed to pick up a ufo with 45 2w, red, blue, and white. They said a 2' distance is ideal and will create a 3'x3' space. Not sure what I can expect as far as penetration. Looks like a scrog is the way to go.

Brand new to led. Funny, there's still not a ton of info it seems, but I think the potential is so great that one day this will be the preferred method once it gets dialed in. People pass this off as a fad. Haha give it a couple years. There's too many growing and security benefits to just dismiss.

Tons of info. I read forever on the subject and am still picking up things and relearning stuff I forgot.

I got some LEDs to play with from customhydronutrients.com. That shop sells the OSRAM 1 Watt chips at a better price than the bigger distributors in small quantities. Otherwise Cutter Electronics sells Cree LEDs pre-mounted on the thermal boards.


My current light has these LEDs

Dominant KNOVA (Red 625nm)
Osram LR W5AM (Red 660nm)
Osram LUW W5AM (Cool White)
Osram LD W5AM (Deep Blue 455nm)

My big light will consist of these LEDs

Cree XPEROY (Royal Blue 455nm)
Cree XPG Cool White (5000-8500 K) OR Osram LUW W5AM Cool White
Avago ASMT-AR30 (Red 625nm) OR Cree XPERED (ordered some of these already to play with)
Osram LR W5AM bin 2T (Red 660nm)




I am using 1W LEDs. Best efficience, just less penetration. I have mine 5" above my seedlings and they seem to love it. 3W or 5W emitters might have to be kept 8-10" above smaller plants, its all relative.

I didn't state it as fact that it is most efficient to use reflective walls or diffused lighting, but it can't hurt at all and will help somewhat. If you think about it, the light that would shoot to the sides of the room would get wasted right? So if you put something there to reflect it, that is just recycling the (what would be) wasted light. If you throw a photon of light with nothing to reflect it, it gets lost out in space. If you throw a photon of light and an inch away from it there is a reflective surface, it will bounce back in a different direction.

So having your LED light covering the whole room plus having reflective surfaces just keeps the light in the cab. I'm sure the energy that is wasted in the deflection of the photon will ultimately lead to less penetration, but the closer your walls are to the light, the better they will bounce and at least provide that extra light on the edges of the room where its usually shaded by other plant leaves. Since my light is about .5" away from each wall, it gives off a nice shine. This morning I notice my middle two plants reaching for the wall I think. If this has something to do with the reflected diffused light then it may be true. I am gonna let em reach for whatever they are going for until I find out what they are going for. I never saw a plant just grow sideways like that on its own. I figure it has to be reaching for something, they are reaching opposite my air flow. I will snag a pic when I get home and check on them. Maybe its just a weird fluke.




I used a metallic silver paint that has little flakes in it. It seems to reflect the light but also diffuse it. I read that diffused light sources are better for growing. I don't know that as a fact, but I am trying it out. Rather than pure reflective Mylar I went this route.

Here are my plants since yesterday. Coco is also good to use with LED. Less heat means more time for evaporation. Coco is great at not getting waterlogged and might be easier to judge on when to water. I water every 1.5 to 2 days. Soon it will be every day now that these seedlings are taking hold.

You see the stretch I got before my 1st fan leaves? This was with this light all the way up by the roof. My oldest plant started its third node and the stretch seems to have went away. So 1 watt LEDs should still be fairly close to the plants or they will reach hard.

 

[GeorgeWBush]

Yeah I've been running coco for a while now. Love it!

My thinking was always to completely cover the growing space with reflective material, but to have as much direct light contact as possible because lumens deteriorate every time it bounces off something.

Looking good smok4. Keep us updated I'm curious to see the 1w LED perform.

I'm still looking for any input on the 2w LED's and how much penetration can be expected with them. 6 inches? Anybody using them?

 

[budlover123]

if you have an LED that you run at 1 watt (350mA), it will penetrate about half as much as that same LED run at 3 watts (700mA) When it is run at 3 watts it emits double the light but more than double the watts (and I also heard watts = heat, so probably more than double the heat too)

If you have two 1 watt LEDs, they penetrate as much as one 3 watt LED but at 2 watts instead of 3 as I understand it. It's hard to say what costs more because you need the same amount of drivers to power half as many LEDs at 700mA than you do at 350mA, and the LEDs will likely have a longer life running at 350mA. In the long run, twice as many 1 watt (350mA) LEDs might be cheaper. Plus, I think you need to use fans pretty much if you go 3 watt (700mA)

If you have a 700mA driver, just make 2 balanced parallel circuits of LEDs that both connect together at the driver and each circuit will receive 350mA at essentially half the voltage. The voltage is split between circuits I believe, correct me if I'm wrong, like if the driver outputs 24 volts, you can run say 6 leds at 700mA with 24v, or 12 leds at 350mA with 24 volts if they are arranged in 2 parallel circuits of 6 leds each, check out the diagram, its from a xitanium driver datasheet, modified slightly to show a driver working powering LEDs at 3 watts in the first picture next to the same diver putting forward 700mA but splitting it into 2 circuits at 350mA, powering LEDs at 1 Watt each, but there's twice as much. That's practically a 2 watt LED setup that emits as much light as a 3 watt setup, but the light is diffused better, which I would think would offer better penetration. (HeHe, He said better penetration) did I hear Beavis and Butthead are coming back!?

sm0k4, have you ever tried neutral white leds? I had a light with red and blue 1 watt leds a while back and when I installed a couple of neutral whites towards the center they immediately turned and faced he center from that point on! I'd give them a shot, maybe the plant appreciates the neutral light because it has more green, yellow, and orange to balance out the spectrum a bit, that was my last attempt to grow and it got stopped about 2 weeks after I installed the neutral whites unfortunately.

 

[sm0k4]

if you have an LED that you run at 1 watt (350mA), it will penetrate about half as much as that same LED run at 3 watts (700mA) When it is run at 3 watts it emits double the light but more than double the watts (and I also heard watts = heat, so probably more than double the heat too)

You are speaking in too general of terms. It gets a bit more involved than that when it comes to actual irradiance value to the garden. But yeah, 3W emitters will be brighter, but have less efficiency so that results in the heat.

I would get an aluminum heatsink profile if I were to use these. I mount 1W emitters on my DIY heatsink and it can get warm. Id imagine 3W emitters would scorch it unless I put less 3W emitters on there.

Now onto efficacy. You want the most distribution of each wavelength across the canopy correct? The 1W emitters, being more efficient, have higher efficacy. Efficacy refers to the amount of light or luminous flux a lamp produces, usually measured in lumens, as a ratio of the amount of power consumed to produce it, usually measured in watts.The assumption and theory which KNNA then proved was in order to achieve greatest efficacy was to use the 1W emitters at a modest spacing. 1.5"-2" apart evenly across the canopy. The problem lies in that you are limited to a SoG-like grow of under 3 feet (I'd stay closer to 2') tall. Obviously you can achieve more wattage with less LEDs if using 3W, but then what about efficacy and irradiance? You now do not have as great of light diffusion throughout the room.

Just food for thought. There is way more to light than throwing wattage at it. In the end it doesn't matter as long as it grows the buds you like. If it doesn't, look into why.

If you want to go tall, use HPS as top light and LED bars as side lights to really fill the buds.
Or you can go LED top light with 3W emitters and LED side lighting with 1W emitters.

For my garden, its only 15" max that I can raise my light, 1W should be ok in my situation IMO. Only growing to a little over a foot tall in here anyway.

 

[sm0k4]

sm0k4, have you ever tried neutral white leds? I had a light with red and blue 1 watt leds a while back and when I installed a couple of neutral whites towards the center they immediately turned and faced he center from that point on! I'd give them a shot, maybe the plant appreciates the neutral light because it has more green, yellow, and orange to balance out the spectrum a bit, that was my last attempt to grow and it got stopped about 2 weeks after I installed the neutral whites unfortunately.

Nope, I use Cool White. Anything with over 6000 K color temperature.

LUW W5AM from Osram are nice
Cree XPG Cool Whites are top of the chain for whites

 

[sm0k4]

If you have a 700mA driver, just make 2 balanced parallel circuits of LEDs that both connect together at the driver and each circuit will receive 350mA at essentially half the voltage. The voltage is split between circuits I believe, correct me if I'm wrong, like if the driver outputs 24 volts, you can run say 6 leds at 700mA with 24v, or 12 leds at 350mA with 24 volts if they are arranged in 2 parallel circuits of 6 leds each

You got the right idea. The bolded part is worded wrong though. The voltage is the same, and the power adds up with parallel strings.

You can output as much as the driver will allow. My driver chip is 25W max. I have 8 LEDs in each string on my light. At 630mA that is 13.5W per string. So I decided to hook two strings in parallel giving me 27W at 630mA. I'm over driving my driver, but its not hot because I have my voltage set so nothing is wasted. I am going to keep going like this until it dies. I wouldn't overload commercial drivers.

If I had a 50 Watt driver, I could connect 4 of my strings in parallel. As long as they operate at similar voltages so you aren't stressing the driver. Something you need to pay attention to if you don't split red from white and blue.

 

[GeorgeWBush]

I have a ufo with 45 2w led's, red, blue, and white. The manufacturer says this consistently outperformed the old generation ufo's they used to sell, with 90 1w led's. Don't know the details about that, but I used to have a ufo from a different company using 1w and from what I remember it seemed brighter.

The company, HTG Supply, says that ideally the light should be 2' away from the canopy, creating a 3' square (or round I guess) growing area. It doesn't seem like the light would be strong enough at that distance.

I suppose I'll give it a try the way it's recommended, but it seems to me like it should be 12 inches away.

 

[420ish]

i have two of the older ufos and 2 feet away is too far for those.is the ufo the onl;y light you are using?how many plants are you going to use that light for?three by three is going to be way too big a foot print for that light.i mostly have used mine for veg and they work great.i have used them to suppliment my hps and or pll's .my 2 watter i only have used to veg and it does alright for an ebay light.am about to take the plunge and make my own as per knna's instructions!

 

[VerdantGreen]

all my LED lamps are 1w .

i have a 60w 60 degree one and its quite capable of bleaching plants at about 4-6".
and i have a 100w one with 90 degree lenses. this spreads quicker and the plants can go a bit closer.

i get 1 gpw or more out of both of them...

 

[budlover123]

You are speaking in too general of terms. It gets a bit more involved than that when it comes to actual irradiance value to the garden. But yeah, 3W emitters will be brighter...

That's a good point, running an LED at 1 Watt or 3 watt really doesn't tell you if the LED is an efficient, good LED or an inefficient, crappy LED, but generally the 1-3 watt LEDs are pretty bright, but I guess without the Bin number of the LEDs and the data sheet that tells you how bright that particular bin number is, you'd have no idea.

I'm sure there are LEDs that are brighter at 1 watt than some are at 3 watts, so that's something to look out for.

I wonder if the 2 watt ufo light is just a slightly overdriven regular ufo light, does it get hotter than the 1 watt ufo?

 

[GeorgeWBush]

No the 2 watt LED ufo doesn't get hot at all. If I put my hand on the lights themselves it feels just lukewarm.

What is known to be a good commercial LED light?

If yo know of a few different ones please list them, and what your experience has been with it. THanks.