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Lighting question

Discussion in 'Growing Marijuana Indoors' started by BoomRuckus, May 6, 2020.

  1. #1 BoomRuckus, May 6, 2020
    Just got my new Spider Farm SF4000 light today. About to get it setup and wanting to get my lighting dialed in perfect. Does anybody have the conversions for umol > LUX > Fc. Also, what are the recommended levels of each for maximum yield in Veg and flower, without stressing the plants?
     
  2. #2 Talkative, May 6, 2020
    30,000 lux to 40,000 lux is how I run. The lux meter is quite helpful. I find if my lights are at full blast, 45000 is too intense, and it is only a matter of inches between 40,000 and 45,000. I have my two 135w boards turned down to 100w each, which I believe is where the spider farmers are set. And at 100w, 30,000 is 18 inches.
     
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  3. #3 Evilsurfer, May 7, 2020
    Migro on YouTube did a 10 minute conversion video. For 3500k led colour temps it was X .023 to give you rough ppfd readings.

    I've run up to 75000 lux with no real issues, but probably not the most efficient. I agree that 40000 is about right which I think was about 800ppfd.
     
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  4. #4 wEEDhEAD1, May 7, 2020
    Lux isn’t really a great tool for measuring led but I think general is 60/65k. But for example last two I took down 1 canapy had some tops at 90k and the other 140k And they both finished fine.
    Best just to start at recommenced and eye from there.
    Light dissipates crazy quick ft by ft. So if the top of your canapy is 50k a ft down could be 10. Play around with a meter if you have one it’s surprising.
     
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  5. #5 BoomRuckus, May 7, 2020
    Awesome. Thanks for the advise. I have the canopy right around 40k-45k now. So hopefully everything goes well. Huge difference from my previous light to QB. Its almost like a real sun in my tent. Cant wait to see the difference in yield.
     
  6. #6 Megadethcloud, May 9, 2020
    QB96=actual sun.
     
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