Great information, but the LEDs are not that narrow, or am I reading you wrong.Those narrower ones if used in excess, can and probably will cause stunted growth and bleaching.
630nm, and every other color are like that too,
and for the most part, all blue LEDs are very narrow and only cover 2-5nm per each,
so if too much blue is used, not only will you stunt your plants, they will probably bleach too.
Great information, but the LEDs are not that narrow, or am I reading you wrong.
Looking at the chart I would say 75% of the light is 50nm wide
Luxeon Star Royal Blue
Source click image:
Now lasers on the other hand they are narrow.
I wonder how a seedling would act if illuminated by a red laser though a widening lens.
Source click image:
Green4me2 - "I have built a couple panels and have had moderate success"
Can we seen them, or are they secret
The LED Tomato Test
Ranking:
1) uv + red + blue
2) red + blue
3) red + blue + green
3) red + blue + yellow
4) red + blue + orange
Wow great info everyone! I am not exactly convinced just yet on the full range leds yet either, but i see and understand both sides of the argument and I cant decide if one i truly superior to the other.
My last panel did just as Eraserhead described. It stunted growth and i believe it may have been due to an overload in blue and violet leds.
Eraserhead in your experience what do you prefer for a ratio of 630nm to 660nm leds? Given the thought that both the 630nm and 660nm leds emit equal amounts of radiant energy. 2 660nm leds to 1 630nm led? Or do you consider that to be to much 660nm?
Thanks! I really appreciate the advice, now its time to save up and build another panel.I would try to get at least one more red color in between the 630nm and 660nm, such as 640nm. I'd do the ratio as follows: 630:640:660 2:2:3, if you went with just 630nm and 660nm, I'd do 630:660 2:3
If you add cool white into the mix, I'd do cool white:630:640:660 3:2:2:3, or cool white:630:660 2:2:3
And it certainly shows, all I'm asking for is some kind of semi-scientific test.I think that tomato test could have been done better. They limited their testing to just a couple color mixes, and no where is there any white. If they used white + red + farred, it would have trumped all the other results, even blue + white + red + farred would have done better for them.
All my info on spectrum is based on looking at spec sheets from manufacturers, and also personal experiments.
I've been studying and researching LEDs for a few years now, and just recently started selling them.
Besides the white LEDs I use, the reds have a 10nm width each, and 5nm with the blues.
Like every LED on the market, one will vary from one to the next, I've looked at the Illumitex LEDs, they are for sale in a few places, I never looked at their specs because the cost is not practical yet and they do not interest me at this moment, but maybe theirs is made up differently, they definitely use different kinds of LEDs, there is multiple smaller chips making up the entire bulb, there could very well be more than 1 bin in there to complete a fuller spectrum, almost positive that is the case.
That sounds like a conversion that could have loss, so the question is why not just use green led's instead,The white color[In white led's] is obtained by using a blue LED and covering the enclosure with a phosphor
that fluoresces in the white. Different types of phosphor coatings give different "colors" of white: from blue-tinted cool-white to
So the question also becomes: Is it best to buy 100 pcs no names led's ind one bulk or 20 pcs 5 different places to get a batch mix of a kind ?
On this I'm reading:
That sounds like a conversion that could have loss, so the question is why not just use green led's instead,
is it the white led's wide spectrum that are beneficial vs. the narrow band of the green led's.
There is, if your human, and not a plant, I was about to say there is that dirty word again "Lumen"There is no gain in light output from a blue to a similar white LED, most likely there will be a small loss.
From my former researches I found out that for instance the Osram Oslon SSL Pure white LED has a radiant output efficacy of 387mW/W whereas the royal blue LED in the same series outputs 460mW/W (for average bins).
"There is no gain in light output from a blue to a similar white LED, most likely there will be a small loss."
This saturation point I take is this:White LEDs might be better in high power panels because there would be less "saturation"
as the light would be distributed over a larger spectrum.
But to reach the light saturation I think it would take a very powerful light already.
I imagine photons as spinning balls, blue rotate faster than red, chlorophyll can only absorb spinnings balls with a certain rotation speed,I do not seem to understand this fully. Does that mean that the 450nm photons (for instance)
carry a large amount of energy but as soon as they hit the plant leaves this energy drops to a lower level
-- the level of energy that 700nm photons have? If such energy is lost, where does it go? Isn't it used by the plant?
I am in full agreement, but many are brainwashed against it. Would love to know if you do a thread on it.Personally, I would buy LEDs from as many places as needed to achieve the spectrum you are after. Whether it is 1 place, or 10 places. As far as no-name LEDs, if I were even to consider them, I'd look at a couple and test them out before buying 100's of them. If you are building your own panel, Cree, LEDengin, Osram, and Philips are good places to start your searches. Mouser.com has lots of cool selections of different LEDs.
As for the green LED as an alternative to white, I wouldn't agree. If one were to take a monochromatic approach to building an array, I would use very little blue, but spread over 2-3 colors, then green, yellow, amber, orange then all the red and farred.
White LEDs provide all the necessary colors between 500-600nm that just a green on it's own cannot, even 2 greens, a yellow and amber wont replace a white.
White LEDs are created from blue LEDs generally, but there is no loss in output, actually a gain if you look at the other colors made by adding the phosphorus. The blue may provide 50 lumens @ 3v 700mA, but that same LED with phosphorus may cut the blue down to 15 lumens, but adds another 200 lumens in other colors, driven at the same 3v 700mA.
Would an all white LED work for flowering? Unless it is a top bin 5w Cree XPG warm white, or 5w Samsung white http://samsungled.com/eng/product/prdHighPower.asp?sSearchTab=C, I would say all white LEDs would be a failure in flowering. I do think an all 4000-6000k panel would do wonders in veg. I'm actually going to be testing a 100w 4260k panel, and will attempt flowering with it just to see what happens. The light is on the way right now.
great info, gonna follow this formula for sure. Just had 2 question tho, is cool white all you need? would i gain any benefit from throwing in some neutral and warm white in the mix?The ratio between 630nm and 660nm....
The most important spectrum that is left out in a lot of LED grow lights, is the 500-600nm area. 65% of the color I use is from 620-670nm and 720-740nm, 10% to 400-500nm, and 25% to 500-620nm.
White LEDs are a great thing, you could easily omit all the blues and greens if you use them, and swap them for a cool white LED.
great info, gonna follow this formula for sure. Just had 2 question tho, is cool white all you need? would i gain any benefit from throwing in some neutral and warm white in the mix?
you also mentioned in a later post about an all white veg panel, what ratio of whites would you suggest for that? I spent my summer working at an organic farm, and now i cant eat the produce from the stores. It is just awful looking in comparison, so i was thinking of starting a lil mini LED vegetable garden to feed me and the fam. So i plan on using the all white panel just for leafy greens like kale, spinach, and other salad mixes. Thanks in advance for the advice, ive been quitely watching your posts, and your one of the most thorough people ive seen when it comes to LED's.