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  • AscPete
    commented on 's reply
    You're welcome.
    I'm attempting to help dispel some of the perpetuated myths about LED's

  • AscPete
    commented on 's reply
    moonfruitgoblins ,

    All (100%) of the light produced by White LEDs is in the PAR (Photosynthetically Active Radiation = 400-700 nm, ~ +/- 95%) or PBAR spectrum (Photo-biologically Active Radiation ~ 300-800 nm, ~ +/- 5% above 700 nm)

    Lumens or Lux directly equates to PAR, PPF or PPFD respectively for All Grow Light Sources...

    For White Grow light sources (UL and or DLC Listed) Labeled Lumens and Digital Lux Meters can be used to measure and calculate PPF and PPFD, Red/Blue LED Grow Lights could also be calculated but it gets complicated because of the Custom Ratios of "Colors", its much easier to use an actual PAR Meter or Spectrometer to do actual measurements.

    There are Lux / Lumens to PPF / PPFD conversion factors for all "White" Grow Light sources
    https://www.apogeeinstruments.com/co...n-ppfd-to-lux/

    For 2700K to 5000K Phosphor-Converted LEDs the conversion factor is 0.015 PPF/Lumen or 0.015 PPFD/Lux
    https://www.biorxiv.org/content/bior...89280.full.pdf

    The Actual LEDs (Light Emitting Diodes) can either be put close together in "COBs" or separated like the HLG boards, but are still currently the most electrically efficient light source. The HLG type lights have the added benefit of better footprint coverage and higher efficiency, at only 120 Lm/W output its better that the highest efficiency HPS HID Lamps..

    https://www.ourfigs.com/forum/figs-h...-and-led-tubes
    https://www.ourfigs.com/forum/figs-h...nd-high-output

  • moonfruitgoblins
    commented on 's reply
    AscPete. I have heard it's basically the overkill of the lumen output that makes the LED growlights work so well. But you need many many lumens to get this overkill in order for the LED to be effective if most of the wavelengths are unusable right? I know people have made their own growlights quite cheaplyfrom Samsung diodes bought on Alibaba, but they still use like 300 of them in the builds i've seen.

  • AscPete
    commented on 's reply
    moonfruitgoblins ,

    Standard Phosphor-Converted LEDs (current generation Samsung LM301's and Household Type LED's) have Spectrum, PAR and Efficiency that are equivalent or better than most "Grow Lights" and are only 8% - 10% less electrically efficient than current generation "Top End" Red / Blue LED "Grow Lights".

    Academic Research has proven that;
    2700K and 3000K LEDs are equivalent or better than HPS...
    4000K LEDs are equivalent or better than CMH and CW Fluorescents.
    5000K LEDs are equivalent or better than MH and Daylight Fluorescents.

    Standard White LEDs are used in many commercial "Full Spectrum" LED grow lights...
    e.g., https://hubbellcdn.com/brochure/hil_0401_cgs_ref_16.pdf

  • moonfruitgoblins
    commented on 's reply
    Ky_Fig, in that case, you could probably get by with some of the lights AscPete is mentioning. I actually just got some nice ones for the garage at RuralKing recently. Extremely bright and cheap, but I am unsure if they put out any of the sort of light wavelengths necessary for plant growth. I know Walmart used to have a plant light that was just a ~14" tinted fluorescent that was maybe 12 bucks. It did fine for starting seedlings and heat was not an issue.

  • Ky_Fig
    commented on 's reply
    Wow. Very informative response. Thank you

  • AscPete
    commented on 's reply
    Ky_Fig ,

    The most cost effective for 12” x 48” coverage footprint for Fig cuttings is four 4000K T8 LED tubes in T8 Shop light fixtures or 2 two bulb integrated LED Fixtures (4000 Lm each Fixture). An 18” x 48” coverage area would require 6 tubes or equivalent. Good luck.

    BTW, the light spread from the fixture shoul be no more than 180 degrees for highest efficiency, more light directed down to the plants. And bare PCB LEDs without diffusers or lenses are all 120 degree light spread.

  • AscPete
    replied
    Ky_Fig

    The problem with the majority of "LED Grow Lights" available on *mazon is that they are mostly sold on "Marketing Hype". The lower to moderately priced red / Blue LEDs have poor efficiency and low outputs (efficacy measured at 0.9 - 1.5 PPF/W maximum), have little to no information on their actual coverage and PAR output. The White LEDs also have little available information, but at least they can be readily compared to easily measurable values (known or measured Lumens)... You can extrapolate (calculate) the outputs of most of these lights by multiplying the actual input watts by an efficacy factor. The integrated "LED Grow Light" fixtures with 3000K to 5000K LEDs are similar to (same as) Integrated LED Shop Lights or T8 Shop Light Fixtures with LED bulbs and often cost over 50% less than the same (similar) *mazon Grow lights. You should select LEDs with over 100 Lm/W for an efficacy of 1.5 PPF/W (100 Lm ~ 1.5 PPF for 2700K - 5000K LED)

    https://www.amazon.com/dp/B07LGTJQ2S..._1AMjEbEZZGND6
    The linked fixtures have an input of 4000 Lm, 36 Watts with 1.66 PPF/W efficacy for a total calculated output of 59.7 PPF each which is equivalent to two (2) 2100 Lm, 18 Watt T8 LED tubes at 1.75 PPF/W each (or 63 PPF for 2 bulbs).



    For example these A19 Miracle LED Grow Bulbs on Sale for $15.00 each have similar (same) PAR Spectrum and PAR outputs to $1.00 5000K (9 Watt x 1.5 PPF/W = 13.5 PPF output) A19 Household LED bulbs available at many local stores, the Household LED bulbs have UL Listings and Warranties. BTW, You can even purchase 15 Watt LEDs Locally, with over 2 times the PAR output for only $1.00 each (15 watt x 1.7 PPF/W = 25.5 PPF).

    https://www.amazon.com/gp/product/B0...c=1&pldnSite=1
    The linked fixtures have an input of 35 Watts with at most 1.5 PPF/W efficacy for a total calculated output of 52.5 PPF each which is less than two (2) 2100 Lm, 18 Watt T8 LED tubes at 1.75 PPF/W each (or 63 PPF for 2 bulbs)
    These GE LED Grow Light bulb has an efficacy of 1.8 PPF/W with an input of 9 Watts, 16 PPF total output...
    https://www.amazon.com/GE-Lighting-9...9641366&sr=8-5

    Legend:
    (PAR) ... Photosynthetically Active Radiation
    is the wavelengths of visible light between 400 and 700 nanometers (nm). This waveband correlates with the energy of photons that can stimulate photosynthesis in plants, frequencies outside of this range are less or not effective for photosynthesis. Phosphor type LEDs emit the majority (most) of their light in the PAR waveband, up to ~ 97%, the remainder is emitted as Far Red frequencies.

    (PPF) ... Photosynthetic Photon Flux
    is the total amount of PAR light emitted from a lamp, abbreviated as µmol•s-1 or µmol/s, (micromoles per second). This value is usually measured with expensive integrating spheres which captures essentially all photons emitted from a lamp (essentially correlating to Lumens). A heuristic for 2700K to 5000K LEDs is 100 Lm ~ 1.5 PPF

    (PPFD) ... Photosynthetic Photon Flux Density
    is the PPF incident upon a square meter (m2) abbreviated as µmol•m-2·s-1 or µmol/m2-s, (micromoles per square meter per second). the value refers to the intensity of PAR at a horizontal surface, which is usually measured at the top of a plant canopy (essentially correlating to Lux or Foot-Candles)

    (PPF/W or PPF/J) ... PAR Efficacy
    is the number of µmol•s-1 (micromoles per second) emitted per Watt or Joule input.

    (Lumens / Watt or Lm/W) ... Luminous Efficacy
    is the number of Lumens emitted per watt of energy. (One Lumen per square meter equals one Lux, and there are 10.76 Lux per foot-candle.) This value refers to the efficiency of a lamp at emitting light visible to people, but can be relevant for plant applications when comparing the energy efficiency (or calculated Par Efficiency) of white LED lamps. Higher Luminous efficacy usually equals higher PAR Efficacy.

    (CCT) ... Correlated Color Temperature
    is the color appearance of light emitted by a lamp, measured in degrees Kelvin (K). Lamps with a CCT below ~ 3,000 K are considered Warm (more red wavelengths / frequency) while those with a CCT above ~ 4000 K are considered Cool (more blue wavelengths / frequency). This metric is actually relevant for Phosphor-Converted type White LEDs and used in plant photo-biology applications for PAR calculations.

    (CRI) ... Color Rendering Index
    is how well a light source reveals the colors of various objects compared with the "highest" CRI value 100 of natural daylight, White LEDs can have values greater than 90 and most household bulbs are greater than 80 but lower CRI white LEDs have less "Green wavelengths" and may provide more PAR from the Blue Wavelengths with High CRI having more Red wavelengths, otherwise its not extremely relevant for plant growth.

    Leave a comment:


  • Ky_Fig
    commented on 's reply
    I'm not looking to break the bank, so what light would you recommend for a couple of plastic totes full of cuttings? Probably won't be implementing a light for at least a couple of weeks (some are just now starting to get leaves coming out) and will probably only be used for a month or so, or until I can move them outside.

  • moonfruitgoblins
    replied
    As a big indoor grower of many types of plants, be weary of cheap LED grow lights, especially "blurples". LED tech has made leaps and bounds since the days of the "LED UFO" that was a big expensive dud in the medical marijuana grow scene (so much so that it tarnished the reputation of LED growlights for quite some time).

    I have used T5's, the BIG CFL's, HPS, Quantum Board LED, Blurple LED (a Viparspectra 300 that was on sale for Amazon Prime day for 50 bucks. its actual wattage output is closer to 120watt, but for the price it's a great little light for clones and such).

    In my main tent I run an Electric Sky ES300 on my high light side, and on the other side where my lower light plants reside, I use a couple T5's (planning to replace them for higher efficiency light soon) and the Viparspectra I mentioned. the low light side is powered by both low end lights, but for my intentions in using them, they're great.

    There's a new LED guy in town who has been causing a stir in the LED Grow-light scene with his very cheap (compared to the high end stuff) lights, which some claim are as good as one of the very top market leaders, HLG (Horticultural Lighting Group).
    https://www.amazon.com/Spider-Farmer.../dp/B07TS82HWB

    This will grow full blown plants, not just seedlings, and is dimmable. I have heard many great things about them.

    Be careful about claims you hear about in the LED grow light adverts. When it comes to grow lights, pay attention to PAR moreso than lumens, and also remember color temp and spectrum of the light is very important. For example, if you were to start baby tomatoe plants under a light such as an HPS (which have low color temperatures), you would encounter a lot of stretching and get lanky plants.

    Leave a comment:


  • T.Frank228
    replied
    Had good success with cheap "alien" LEDs from amazon:

    https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

    Been going strong for 2 years with no problems. I run only maybe 3 months a year or so though.

    Leave a comment:


  • Dtownfigs
    replied
    I just bought and recieved the HLG 65 from amazon $99 on prime and WOW is it ever bright!!! I’m adding it to a few Feit eletric lights that I bought at Home Depot last season which allow you to toggle red, blue and white Options. I also have a strip of A19 to add additional light, but the HLG 65 is stupid bright and wonder if I’ll even need to run them. The design this minimalist and really appealing. 4000K, wish I would have started with these as opposed to the Home Depot lights I bought for almost as much ($65 each)

    Leave a comment:


  • Enscribe
    replied
    I have been using the "alien" lights for two years and have nothing to complain about except the color. Mine are 1foot square $30 Amazon lights, 45w but probably draw light 18w. They are able to produce a better quality green plant growth than florescents and they can be far above the plants and remain effective.

    After rooting, I usually switch my cuttings to either a 250w or 400w HPS. This year I'm switching to dual 300w LED's. I expect good things. Setting them up right now.

    Leave a comment:


  • Kevin912
    replied
    I've been happy with these so far
    Attached Files

    Leave a comment:


  • Kevin912
    commented on 's reply
    I'd say not what you're looking for.. it appears they have plastic covers around the light bulbs which prevent the light from reaching the canopy of your plants. 50 watts per square foot is ideal. There are much better options on Amazon for dedicated grow lights
    Last edited by Kevin912; 01-20-2020, 11:39 PM.

  • cepeders
    commented on 's reply
    I second this. I have 3 4'X8' shelves now using $1 and $2 15 watt LED bulbs on the outdoor string lights. The plants are doing great.


    It is very economical and just as effective as my higher end grow lights for cuttings.

  • Ky_Fig
    replied
    I was looking at possibly grabbing these:
    https://www.amazon.com/dp/B07LGTJQ2S..._1AMjEbEZZGND6

    Doesn't seem a bad deal. I only have a couple of bins of cuttings and I thought 2 lights @ 4,000 lmn each at 5000k would probably be sufficient. Give a couple extra light to you around the house.

    Leave a comment:


  • AscPete
    commented on 's reply
    I agree.
    I've been using E26 base LED bulbs (DIY with outdoor string light fixtures) for grow lights and they are comparable to the HLG LEDs with similar CCT...

    Migro LED has produced several comparison videos of different technologies, CMH/LEC has proven to be very efficient and economical, a close second behind properly designed LEDs like the HLGs; https://www.youtube.com/channel/UCSZ...xS54qdA/videos

    My preference is standard Household E26 base LED Bulbs that can provide more that adequate amounts of light at higher efficiency than several commercially available fixtures (~ 1.7 PPF/Watt), i.e.;
    7 - 100 Watt Equivalent A19 LED Bulbs
    10,850 Lumens, 5000K @ 91.0 watts (~ 157 PPF).

    Spectrum King MLH video; https://youtu.be/IjY2FuNNxKQ
    10,000 Lumens 5000K LED @ 101.0 watts (~ 145 PPF)

    HLG-65 video; https://youtu.be/aHFyCvoAIAA
    10,000 Lumens 5000K LED @ 65.0 watts (~ 145 PPF)

  • bent
    commented on 's reply
    Thank you! Yes, I could see how T8 LED replacement bulbs would make a lot of sense as well. I might do a little experimenting this winter; my current set-up is barely functional. I'm going to re-think my lighting.

  • AscPete
    commented on 's reply
    Don't have any T5 fixtures, but have used 4000K and 5000K T8 LED tubes (Philips Instafit - 123 Lumens/W) in T8 shop lights for ~ 50% increase in light output and 1/2 the power use compared to the T8 florescent tubes in the same fixture (measured with Lux and Watt meters)...

  • Foodtreefield
    commented on 's reply
    Bought some of the cheap Chinese LEDs last fall (5) and by spring only two of them were operational. (The UFO style). Lesson learned. The better ones seem to be the cobb type. Lasted over a year so far.

  • bent
    replied
    Has anyone used the 4' LED T5 (5000 Kelvin) replacement bulbs in their T5 fluorescent fixtures? I assume they would work just as well as the Fluorescent T5 tubes and use half the power.

    Leave a comment:


  • Nomnoms
    replied
    I plan on growing my cuttings indoor permanently in a shed or garage, what light should I use? I don't want to change out bulbs for different stages of growth, is there a light that does it all?

    Leave a comment:


  • dimitri_7a
    commented on 's reply
    With proper cooling and reasonable quality manufacturing LED failure rates are very very low. When was the last time an indicator light (power button light?) went out on one of your electronic devices? They even make Chip on Board (COB) LEDs which are arrays of dozens of LEDs combined into one light.

  • dimitri_7a
    replied
    LED technology has gotten crazy cheap and efficient in the last couple years. You can get a ready to use fixture for as little as $75 shipped (https://www.amazon.com/VIPARSPECTRA-.../dp/B01B4GQ6MO) or $100 if you prefer more natural looking light (https://horticulturelightinggroup.com/products/hlg-65). Keep in mind these are very powerful lights that can be used to grow a respectably yielding tomato / pepper plant or provide enough coverage for 4-6 sqft of growing leafy greens / cuttings / seed starting - and unlike florescent bulbs you can hang them as high as 1-2' from the top of your plants versus a couple inches. Really though, LEDs have a lifespan of 5-10 years before they lose any significant amount of brightness/efficiency which is 2-3X longer than any fluorescent bulb and they are also 2X more efficient than T5s & T8s at producing light.

    Leave a comment:

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