This is why i posted the link to the panel i bought. Most newbs to LED arent going to drop 1k on a lighting setup and will look for something like the unit i purchased. Just a friendly warning, and not stating that LED is useless and cant grow a good product. I agree the unit i purchased is of low quality.
L.E.D Growers question! :)
- Thread starter TweedleD
- Start date
Though what you are saying isn't blatantly wrong, it's very inaccurate. You really need to understand led's to get how optics and emitters pair. For instance, 1w emitters with 90 degree optics have better penetration than 3w with 120 degree optics. Think of the optic angles as taking whatever light the emitter is giving, and just changing the way it is spread. The best designed hoods I have seen (the commercial stealth units) mix 3w 120 degree optics in proper chlorophyll a & b peaks, as well as mixing in 1w 90 degree whites for penetration. These perform much closer to high wattage HID's because of the penetration of the 90 degree optics, but allows them to cover the more broad space uniformly like a high quality HID reflector. You'll also notice these commercial units run around $2400 for (I believe) around 3'x8' coverage. Anyway, main issues with buying led's is that it's new technology, it has so many applications that there are thousands of options for even the novice, and you have to understand the technology to make proper decisions, it's just not developed enough to where you can trust vendors or make broad assumptions.
Edit: Err, just noticed I explained something wrong there... three 1w with 90 degree emitters will penetrate better than one 3w with a 120 degree emitter... I hope my original post wasn't too misleading in that regard. Boiled down 90 degree optics have their place, and understanding the subtleties of LED's is what separates the crap from the awesome in LED lights.
This is what I am talking about, and what I think people don't understand. For a few plants, as few as 2, plan on spending $400. To replace a 400w MH, plan on spending $1000. To replace a 1000 or two, you can easily go over $2000. LED's are not cheap. If you can't afford to do them right, you will get WAY WAY WAY WAY better performance out of HID or T5's and usually even CFL's.
Token Winston
Member
Anybody tried this...
http://www.hidhut.com/catalog/ufo-adjustable-enhanced-spectrum-led-grow-lights-p-1828.html
I might buy it but want to know if it is good first. I am looking to start seeds and grow up to 4 short autoflower plants.
http://www.hidhut.com/catalog/ufo-adjustable-enhanced-spectrum-led-grow-lights-p-1828.html
I might buy it but want to know if it is good first. I am looking to start seeds and grow up to 4 short autoflower plants.
tendran
Active Member
You keep talking about these "mixed spectrum diodes" and I have no idea what you mean. Does each light have the ability to adjust to different spectrums? Do you have a link to something on DesertHydro that has product specs that says anything about special led's? All it says is that it has orange, red and blue wavelengths.
The light I bought has several red wavelengths, uv blue wavelengths and some white/mixed spectrum lights for balance. Not knocking DH's lights, as I've not tried them. Just curious as I did visit their site and their product did not resonate to me as something that stood out from the crowd.
By saying it has orange, red, and blue, it is telling you it has a mixed spectrum. To make it make a little more sense, take a look at http://www.stealthled.com/userfiles/spectrum.jpg. It shows the spectral absorption for chlorophyll A & B. Good grow lights will have diodes that provide the 4 spectral peaks used in photosynthesis. Keep in mind that diode spectrum is measured in wavelength, to say a diode is blue or red or whatever doesn't really tell you much. There are many wavelengths you'd consider blue, or red, or orange.
OK, I'm an engineer embarking on my first grow....LED all the way.
gobbly has the best take on this here but I wanted to add a few of my own observations;
in LED tech it's ALL about focus! Focus on the desired wavelength (something LED's do incredibly well) and focus of light emitted. It's just plain physics and not very mysterious. The narrower the focus the more energy per sq inch. The more energy per sq inch the further away you can get the light. The further away you get it the better the dispersion (blending) of the light. The more dispersion the less 'hot spots' and the more 'natural' the light acts (no sharp shadows, etc).. My suggestion is if you have 120 degree units get them CLOSE to your crop AND make sure you have very reflective grow room. Just remember that reflected light is much less intense than direct. Also, I would suggest turning your plants often to expose all angles.
All things in consideration-A 90 degree is better than a 120 as it focuses the usable energy to the plant. 120 lust lights your walls. Doubt me? Break out your old protractor from high school and do a little experiment. Mount it and run a string out on the 120 degree marks. Do the same for 90 and 60. Now, think about the distance from the plant the light is (even as close as 6" is too far you will see) and see for yourself.
My preference for LED's? 300w quad band panels of 1w LED's. I will be doing either 4 or 9 plants per light and I will be using them for veg too. I MAY add some red LED's for the flowering phase. I suppose I will start a thread on my grow....
Basically LED is very straight forward tech. It's not a mature science but it's not exactly cutting edge anymore. Been around more than 35 years now! Yes, you will need wattage. Pretty much 50% as much as you would need with HID so yeah, it's expensive. I got lucky, I got 4 good lights cheap on craigslist.... $750 lights for $250 each
gobbly has the best take on this here but I wanted to add a few of my own observations;
in LED tech it's ALL about focus! Focus on the desired wavelength (something LED's do incredibly well) and focus of light emitted. It's just plain physics and not very mysterious. The narrower the focus the more energy per sq inch. The more energy per sq inch the further away you can get the light. The further away you get it the better the dispersion (blending) of the light. The more dispersion the less 'hot spots' and the more 'natural' the light acts (no sharp shadows, etc).. My suggestion is if you have 120 degree units get them CLOSE to your crop AND make sure you have very reflective grow room. Just remember that reflected light is much less intense than direct. Also, I would suggest turning your plants often to expose all angles.
All things in consideration-A 90 degree is better than a 120 as it focuses the usable energy to the plant. 120 lust lights your walls. Doubt me? Break out your old protractor from high school and do a little experiment. Mount it and run a string out on the 120 degree marks. Do the same for 90 and 60. Now, think about the distance from the plant the light is (even as close as 6" is too far you will see) and see for yourself.
My preference for LED's? 300w quad band panels of 1w LED's. I will be doing either 4 or 9 plants per light and I will be using them for veg too. I MAY add some red LED's for the flowering phase. I suppose I will start a thread on my grow....
Basically LED is very straight forward tech. It's not a mature science but it's not exactly cutting edge anymore. Been around more than 35 years now! Yes, you will need wattage. Pretty much 50% as much as you would need with HID so yeah, it's expensive. I got lucky, I got 4 good lights cheap on craigslist.... $750 lights for $250 each
tendran
Active Member
I understand the vagueness behind simple color names and the details of wavelengths and what different wavelengths bring to the plants production. What I didn't understand was the claim that no other lights have mixed spectrum diodes. Do you mean to say that each individual led has 3 different wavelengths, or do you simply mean that they combined separate leds, with separate wavelengths (which most manufacturers do as well).
If you meant the former, where is the spec sheet on the bulbs used by DH to back this up? I didn't see any talk about special multi spectrum leds on their website, which is why I'm asking to have this clarified.
breakneck
Calyx LED
Yeah their site is very new. You will notice it says the wavelengths are 620~660&430~470 on all units. I think they are just scared to talk about the new diodes until their patent goes through...makes sense to me.
Serapis
Well-Known Member
Word of warning on good LED units. Do not believe that you can place these lights as close to plant as you wish due to lack of heat. The intensity of the lights can burn your new growth just as easily. While I can't get HTG to give me a solid height, we did agree that 18" was probably good for newer plants. After just 2 hours under one of the Tri-Band lights, I nearly lost 5 new plants that were about 2 weeks old. The light was 10" above the plants. So it is possible to burn plants with these, not from actual heat, but from intensity. Some manufacturers of LED systems say to use 2'. Had I known this, I might have just used my space for HID MH lighting since I have to stay off the plants anyways.
Has anyone else had LED lights "burn" or sear their plants?
Has anyone else had LED lights "burn" or sear their plants?
tendran
Active Member
Don't know what to make of them until I see further evidence. As of right now, I would recommend (and bear in mind I earn no money in making a recommendation) that as far as price, quality product, warranty/repair, efficiency, etc, GrowLEDHydro.com or HydroponicsHut.com.. This is based on a lot of research and sifting through dozens of LED grow journals and a lot of LED topics and not my own experience though, I will say. HTGSupply has also been recommended by many others. Honestly, the photos on DesertHydro.com look exactly like all the cheap chinese models you see all over Ebay.
As far as which light you end up going with, total wattage, etc it depends on your grow space/design, plant count and budget. 90w are better than n0w.
breakneck
Calyx LED
Look at my grow, I use DH's lights. Two of the 300's and I am super stoked on them. Fastest, tightest growth rates I have ever seen in 10 harvests. I have used units from eBay, and from HTG. I actually think DH might supply HTG....I know they sell their lights to a lot of other online stores...
TweedleD
Active Member
Sorry I've been a bit under the radar lately.
Haven't had access to a pc lately.
I've decided to buy a UFO and supplement with some cfl side lighting.
However I am having a hard time finding a UK supplier or website that sell quality UFOs and not shitty Chinese ones.
Any UK LED'ers point me to a good site?
I think that this thread should also be stickied and used as a reference point for anyone looking to grow with LED's.
....just a thought!
Peace
Haven't had access to a pc lately.
I've decided to buy a UFO and supplement with some cfl side lighting.
However I am having a hard time finding a UK supplier or website that sell quality UFOs and not shitty Chinese ones.
Any UK LED'ers point me to a good site?
I think that this thread should also be stickied and used as a reference point for anyone looking to grow with LED's.
....just a thought!
Peace
breakneck
Calyx LED
I have a brand new UFO from Desert Hydro with 1w CREE's I'll sell you cheap...lmk.
Sorry I've been a bit under the radar lately.
Haven't had access to a pc lately.
I've decided to buy a UFO and supplement with some cfl side lighting.
However I am having a hard time finding a UK supplier or website that sell quality UFOs and not shitty Chinese ones.
Any UK LED'ers point me to a good site?
I think that this thread should also be stickied and used as a reference point for anyone looking to grow with LED's.
....just a thought!
Peace
