LED lights guide for beginners by a beginner:)

Discussion in 'Newbie Central' started by Naija, Apr 18, 2017.


    Naija Active Member

    After lots of reading and "research" trying to find the perfect LED light to start my first grow, I came across lots of terms that I felt is important to understand, in order to pick the proper LED.


    LED: light-emitting diode

    Light Spectrum: Light spectrum is the many different wavelengths of energy produced by a light source. Light is measured in nanometers (nm). Each nanometer represents a wavelength of light or band of light energy. Visible light is the part of the spectrum from 380nm to 780nm.

    Infrared > 760nm
    610< Red< 760
    590< orange< 610
    570< yellow< 590
    500< green< 570
    450< blue< 500
    400<violet< 450
    Ultraviolet< 400

    Spectral distribution chart: The spectral distribution chart is a visual representation of the light spectrum produced by a lamp. It is a graph showing the relative intensities of a light source at each wavelength.These charts can be used to compare the energy levels of various light sources. They are the most practical way to compare the quality of light created by different light sources. The chart shows exactly which wavelengths of light (measured in nanometers) the objects are receiving.

    On the left of the chart is the percent of relative energy. The highest energy output of the light source is plotted as 100% Relative Energy. The 100% peak is used to compare the energy levels of all other wavelengths of light produced by that light source.[​IMG]

    The bottom of the chart shows all of the wavelengths of visible light energy that the light source produces. For example, if a wavelength is at 50% relative energy, that peak has half the energy when compared to the 100% peak. Scaling each chart to 100% relative energy allows side by side comparison of light sources with different lumen ratings (intensity) or wattages. For example, a 1000W HPS lamp has more overall intensity than a 400W HPS lamp even though their spectral distribution charts are the same.

    Lumens: In short it's the light intensity, however this measure alone is meaningless when it comes to how "good" or "bad" the quality of the light produced for the plant is. In other words it's a quantitative measure rather than quality measurement.

    Photosynthetically active radiation PAR: is the amount of light available for photosynthesis, which is light in the 400 to 700 nanometer wavelength range.

    PPF (photosynthetic photon flux), or light output: is a measure of the total PAR produced by a light source per second. However, because PPF is measured at the light source, the metric doesn’t accurately represent the amount of light that actually reaches the leaves of plants or the distribution of the light after its emission. That makes it a meaningless measure in grow lights.

    Photosynthetic Photon Flux Density (PPFD): is a measure of PPF that reaches a specific area (m2) of a given surface; in other words a measure of number of photons in the 400-700 nm range (PAR spectrum) that falls on a square meter target. Because PPFD only considers the light that reaches plants, it is generally considered a better metric than PPF, and the metric is currently one of the best ways to measure and compare light intensities. However it's important to know at what hanging height were those PPFD taken; and the PPFD measurements at different spots from the light's covering area.

    I am quite sure I missed more terms and vital measures that make a growlight good or bad, I hope some experienced posters can add.


    Some info I came across, that seemed important in picking an LED grow light, I don't know how accurate the claims are or how vital those points are.

    1) White LED lights that represent the full light spectrum is better than broad spectrum or gap spectrum lights.

    2) There are two types of White Lights;
    2.1) Single LED that emits three primary colors of Red, Green, and Blue, multi-color white LED or RGB LEDs
    2.2) Phosphorus type; phosphorus based semi conductor material that that converts blue or UV light into broad or full spectrum white lights ( phosphorus based white LEDs.

    Claims are Single or RGB LEDs have more stable color, more efficient CRI and better luminous efficiency.

    3) Green light spectrum, I got contradicting info some claimed it's not important for the plants therefore it's a waste, others claimed it's important especially for the shaded parts of the plants.

    4) UV and IR are important to the plants.


    Some questions I got after reading about lights

    1) Since most grow lights have a coverage area of 4X4, why the huge difference in wattage? Do more intense lights have better canopy penetration and get to lower parts? Anyone with any info or comparisons done on this matter.

    2) ideal PAR, PPFD reading for marijuana growth at different stages.

    3) ideal spectrum distribution for different growth stages

    4) for someone looking to achieve the highest yield per plant and not per harvest what spacing do you recommend, and light parameters do you recommend.

    5) any websites or individuals that customize LED lights or does it have to be DIY.

    Any info that would help making the best decision in picking a grow light would be appreciated. There are many brands out there and can't really rely on what the claims are.... picking the grow light has been a major headache lol

    Ty all in advance

    Nugachino likes this.

    Fevs Well-Known Member

    That looks like a bollocks spectrum for led! Piss poor!

    Keep looking... look at the cob threads man...
    714steadyeddie and Naija like this.

    ZxcStaz Active Member

    I have used full spectrum LED's in addition to CFL's, MH's, and HPS. I incorporate a combination of lights throughout the grow. When I used high wattage, full spectrum LED's during germination the plants burned. The full spectrum LED's have the IR and UV, so the plants need to be hardened off, just like outside. I have found that starting with low intensity lights and building from there works well and reduces electric cost while maintaining optimal growth. In regards to your spectrum question, the blues work well for keeping the girls short and bushy, but you need enough stem length for light penetration later in growth. If you have the room space, let them get a bit leggy in the 4th week so that your LED's can shine onto the lower leaves. The LED's don't have the push to break through the canopy, as compared to HPS. You may get better coverage with the COB LED's, but so far I have found that a hybrid system is boss. This is my empirical data, so it's not peer reviewed; just a suggestion.
    Naija likes this.
    Observe & Report

    Observe & Report Well-Known Member

    I've noticed recently that people don't seem to know what a COB is, what makes it different from a regular LED chip, and why it's better.

    ZxcStaz Active Member

    The Chip On Board (COB) is just the LED's placed tightly on a single small circuit board, usually with a focusing reflector. The LED's have their specific wattage; 1W, 3W, 5W. These are wired in series to create a 50, or 100 watt "chip". These can be Zener protected or not in said lighting unit. The benefit is that the light produced is concentrated in a small area, thus the intensity is increased (as per the inverse square law), so that it travels through the canopy. I believe that this is done to increase the penetration to mimic the intensity of the more powerful HPS lights. It can be loosely thought of like focusing a flashlight beam from a large area of light unto a smaller one.
    Naija likes this.
    Budget Buds

    Budget Buds Well-Known Member

    This has been done on here about 50 times now. use the search function mate
    Fevs and Naija like this.
    Observe & Report

    Observe & Report Well-Known Member

    You should look up what chip on board means and its impact on thermal management and thus efficiency, instead of just assuming based on the name and visual appearance and then passing out bad information. The law that is important here is Fourier's. The inverse square law has nothing to do with COBs.
    PetFlora and Heil Tweetler like this.

    Fevs Well-Known Member

    You should look at the plants people are growing under cobs. Much better and healthier than plants grown under most blurple leds There are some good blurple panels with Osram leds in, but there are many more panels with cheap leds and rubbish spectrums.

    Ignore all the scientific jibberish and look which lights the plants actually like @Naija as growing weed really isn't as complicated as people make out.

    I'm not one of those growers that jerks off over grow light efficiency figures, there are many here! lol

    I grow under cob which is white light, much less chances of making mistakes, as you can see the plants with such clarity. I think all new growers would be better off using White light cob grow lights.
    Naija likes this.

    Fevs Well-Known Member

    Ask yourself these questions.

    What size area do the plants have?

    How much weed do you want to grow?

    What is the ambient temperature of the room you'll be growing in?

    Do you have plenty of fresh air exchange in the growing area?

    What is your budget?

    It would be helpful to know this info...
    Dr. Who

    Dr. Who Well-Known Member


    UV is not applied to plants by LED's that only stop at 400 nm bands.

    Sadly = If you want to add the good UVB. LED banks don't deliver the 280 - 315 nm bands that make up the UVB range!

    I've been interested in LED's but COB's have lower life spans due to heat degradation of the Diode.....I hear there are liquid cooling kits available. Big LED banks with $2500 (and up) price tags? Fucking really?

    For the life span of the LED bank.....I'll spend far less with a ballast and HID lighting. Yes even buying new bulbs every year.
    CMH......I simply have a problem with reducing my footprint down to a 3X3 footprint! Fucks up my room design.....Sooo,,,,,,,I run 400 merc vapors under 1K HPS in bloom. I get all the spectral spread I need and deliver that UVB all at one time.

    Oh, yeah. I have a rare type of hood that actually has reflective ability over the cooling vents - Ones that work right.
    JUPITER 6's the guy who made them did it the right way - you gain 20% of reflected light.....He went out of business and i got the last 16 he had......I had to pry the fuckers from him!
    greg nr

    greg nr Well-Known Member

    Where did you hear COB's have shorter life spans? Just curious because these are designed primarily as commercial warehouse lights and their reliability is well documented (not just in theory, but in use). Growers have adapted them for this niche but it is just a niche. A very small one by the numbers shipped for other uses.

    And $2500 is a retail cost. The bulk of these are being used by the diy market and the chips can go as low as $12 each. You can build that $2500 light for less than a $G. Which I get is still more than hps, but there are other considerations.

    I know there is a lot of hate from the hydro store segment. They hate that even when someone buys an led from them, they don't come back and buy parts for it. You don't need new digital ballasts, you don't need new bulbs, you don't have to replace reflectors (yes, some hid growers change reflectors, glass, and bulbs every year).

    They also hate you no till guys. What with never buying more soil, or nutes, or ph meters. Bad no tillers. Bad. ;)

    I do agree though that if you have 30k sq ft of grow space, you are going to go DE or CMH. But you will also have 15 foot ceilings, industrial grade ac, and more cash than time.

    Don't hate the new, if it isn't for you then great, stick with what works. But LED's and COB's do work well for a lot of growers. It's like hating someone for liking living in a big city. As long as nobody is forcing you to live there, why do you care?
    ZxcStaz and Fevs like this.
    Dr. Who

    Dr. Who Well-Known Member

    I don't "hate" COB at all......I still will play with it in time..

    Heat is any diodes biggest enemy! COB's create more because of the multiple diodes......I see all sorts of heat sinks and such for them. Like I said I'm seeing liquid cooling coming in for them now too! As diodes are exposed to heat. They will slowly reduce in output...Takes a bit to get started but, once they do begin to degrade. They can degrade fast....

    I have to admit that the ceiling heights in commercial ops tend to mitigate the heat problems from DE equipment.....at plant height.

    Naija Active Member

    Well the area I got is a 10X10 tent with 7'11 height, but I am creating to corridors in it each is 2 ft in width so that leaves me with 4 4X4 areas' reason that I am creating the corridors is I am a new grower with no previous experience so I thought it would be nice to have easy access to all parts of the tent and monitor all parts; another reason is I really don't need 100sqf atm; but who knows I might need it later.

    Seriously this is one of the most nagging question currently going through my head, however I do have some major points that might be useful in helping me determining the number of plants, I don't have skills in any of the training methods so I would be doing zero to minimal training, maybe just taking off the lower parts although I am planning to provide light for those as well, on average I would have 3 hours time daily to look after plants, and I'll be using soil; that being said in each grow area (4X4), I am looking at 4-5 plants.. do you think that's good enough or too many plants? How many plants do you think can fit in a 4x4 if you are looking at highest yield per plant,,, and how many can fit in a 4x4 if you are looking at highest yield per sqf.

    Anything other than COB or LED is out of question for many reason, the most important reason is heat where I live the avg temp is 87-90 all year long and humidity is 50% December to March and 70-90% April to November.

    As for the fresh air I have lots of fresh air if needed and I am considering CO2 supplementing; keeping it at 800-1000 ppm lvls.

    I haven't really set a budget; it's more of an open one till I get this fully done.
    Fevs likes this.

    Naija Active Member

    Ty for the reply

    I promise you I've read just about every thread out there, some threads are a bit old, and some never gave an answer to the questions I posted.. if I studied in high school the way I researched lights I would have been politician by now lol

    Ty for the reply

    Thank all, pls any input would be helpful
    Fevs likes this.
    greg nr

    greg nr Well-Known Member

    Not an expert here, but it seems to me given what you stated as your environmental's for that space you will likely need a/c even if you go with led; especially if you want c02. Co2 means a sealed room, which means a/c. 90 degree humid ambient can't be cooled by moving more 90 degree humid air.

    So go with the good doctor's advice and go hps with an a/c. 600w is the conventional advice for a 4x4; add a light mover for a little extra coverage. It's cheap, and certainly has a track record.

    If a/c isn't an option, you will have to scale down, use lower wattage led's, run your lights at night and hope for the best.

    There is a thread on here somewhere about a guy in new zealand who runs int high 80's with no a/c. So maybe its possible.
    Naija likes this.

    Naija Active Member

    Sry maybe I misinformed you, the temp and rh I mentioned are outdoors, but inside the house it's much cooler and less humid, a/cs are always on
    Fevs likes this.
    greg nr

    greg nr Well-Known Member

    Ok, so the heat and wattage savings may not be what you expect. So lets say you would use a 600w hps, and a 400w led. Times 4 you are saving 800 watts of electricity and whatever 800w of btu's turns out to be.

    If that is the tipping point to either major electrical work or major a/c upgrades, you may need led..

    I'm a fan of led. I'm not trying to diss it, just giving you a complete picture. For a 4x4, you could go with Quantum boards, 6 boards, 2 sets at 260 watts each. Add some deep red and it should be good. But it will be more expensive than hps, and you are only saving a 100 watts per quad.
    Naija likes this.

    Fevs Well-Known Member

    Each 4 x 4 area I'd go with four 5-6 gallon pots. Will save ages in veg time, over growing 1 plant.
    Naija likes this.

    ZxcStaz Active Member

    I can't get in "tune" with your statement about bad information. It was a basic description, and an analogous example to simply describe the benefits of proximal spacing. Not bad information, just rudimentary - the thread title " ...for beginners". Distance does matter when considering intensity and penetration, in regards to total power input. This is part of the allure of COB's, in addition to their increased efficiency.
    COB's have shown a 30% increase in efficiency, according to some sources ( not going to reference them, already have my degrees), due to a reduction in thermal waste. If the heat can be dissipated effectively, then increased PAR can be achieved, within temperature parameters.
    Instead of just adding destructive interference, we should construct a well rounded thread so that present and future readers can benefit from our knowledge. Please illuminate us in a constructive manner. That way a full spectrum of wavelengths can be emitted from a few posting members. Peace sine.


    * @ Naija - Thanks, I hope some of my info helps. This is an awesome adventure we are undertaking, and well rewarding. Don't worry about pitfalls, you will be successful with perseverance. Just learn along the way; jot notes, record aberrations, and read. You'll have a grand time.
    Naija and Fevs like this.

    Xcoregamerskillz Well-Known Member

    Just a point about heat, for about 4 dollars you can buy an air cooled CPU cooler that will handle the heat off any LED. You can also find extremely cheap PC liquid cooling.
    Last edited: Apr 20, 2017
    Dr. Who, Naija and Fevs like this.

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