L.e.d. Distance

Discussion in 'Growing Marijuana Indoors' started by Smooks714, May 12, 2016.

  1. So I originally started my clones, with an l.e.d. Light about 22 inches away. Most people recommend 18-24 inches away. Well of course the plant has gotten taller, and I was curious, do I start putting the light farther away. That way I give it some room to grow more, say 30 inches away. Or do I stay at the traditional 18-24 inches away?
    It is about 16 inches away at the moment, and I started around 22 inches away and it's gotten pretty tall in two weeks.
     
  2. Keep moving the light every few days, keep it between 18-24"
     
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  3. Th
    ank you so much.
     
  4. leave a temp gauge at that same height or abouts,

    ensure you don't exceed 27c/77c

    good luck
     
  5. This vid may help
     
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  6. That video is great, and I have definitely seen it on my personal grows using those cheaper Chinese LEDs.

    He's suggesting 12 inches as a good flowering height, I'd agree but raise the light a bit more to encourage some stretch and verticality. The other thing he's suggesting is two medium units is better than one super-strong LED. Again, I'd fully agree with that. He's using 16 inches as his height, with two (what appears to be) bog-standard Chinese units.

    He's also scrogging and that's ideal with LED. A traditional bulb works in all sorts of directions, but LEDs are much more focused.
     
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  7. I keep my led lights between 10/18 inch depending on what lighting regime they are on so 1 8inch in veg and a slow as 10 inch in flower and u have not noticed any bleaching or stress due to the light being thay close??? I have 1 plant under 750watts of l.e.d.s I will post a picture in you are interested
     
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  8. I believe it depends on the light, and the video states it is a cheap LED, so it is not a good rule to go by. My lights have to be 21 - 22 or it will burn.
     
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  9. I do agree the better the light strength further thay need to be. However' I have seen so many vids and read so many journals that range from cheap led setups to the high end led setups and all diffrent strains under them and my conclusion is there are to many factors to give any 1 answer so o say give as many led lights and as many strains as you can and find out for yourself . PEACE YAW!!! 20160818_000240.jpg
     
  10. If the plant is happy and growing vigorously then its perfect, if you notice stretching then place it closer a little at a time,
     
  11. I keep my 180w led at 18" for veg and 12" for flower. She's from 2010 and 1w led's so the newer ones are more powerful and I would increase the distance. You'll find the happy spot. If I can grow dank with 6 year old led technology, your new(er) led can too. I too would recommend s(c)rogging it. Led's don't penetrate like hid's, so a flat canopy is best.


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  12. I've had my lights sat at 14 inch for the 350 znet and 12 inch for the other two and I havent noticed any bleaching as of yet.
    I'm 3 1/2 weeks into flower on this cheese.
     

    Attached Files:

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  13. I have my plants under a 1000 W led. I start at 24'' and slowly work down to 18'' by the end of veg and down to 12'' by the end of flowering by raising the lights slower than the plant is growing.

    I have a post going for my grow and Ill be updating it throughout.
     
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  14. I now have my leds sat about 8"from my tops and she is loving it I think???

    Not long now ' today is he start of week 6 of a 7/9week strain wich I should probrobly add another week because I'm in soil. 7/10days flush starts on the 8th week ish??? Depending on how she looking.... 20160914_225209.jpg at the moment she sits 1/12 feet from my pot wich is a 11litre.
    I wish I would of used the 20litre pot I have but shit happens...
     
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  15. I must agree that this light is not a good one to go by. If you don't have the ability to measure your PAR then sticking with branded LED lights would be the better choice.
     
  16. The light distance is going to vary from different light manufacturers and wattages. Some of the lower end lights can be put as close as 12" but I certainly can't do that with mine. I would say 18"-24" seems to be the sweet spot area for most. Different LED's have different lenses and scatter the light at different rates.

    This other point is the light distance the plant likes can vary with the strain. I have a sativa in my garden right now that seems like it cannot be burned. It's as close as 14" from my light right now and happy where nothing else has been able to get closer than 18 without visible heat stress on the leaf tips or singed off white hairs like it got a flat top.
     
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  17. I use a 749 draw led and keep it 15 inches from canopy most LEDs not all are germination 24 to 30 inches, veg 18 to 24 and flower 12 to 18 inches. I lower the light 2 inches every week while my plants are in flower.


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  18. #18 brianmmj, Nov 13, 2016
    Last edited: Nov 13, 2016
    I recommend you measure the light rather than the distance, unless the manufacturer has a recommendation. Relying on a magic distance is going to be extremely variable. Relying on your eyes is not good because your brain cant tell the difference for a huge range.

    How to measure without expensive custom equipment?

    Your smart phone has a pretty good light meter for photography. There are lots of apps to measure lux. I use "Lux Meter".

    Is it accurate? It doesn't really matter as long as it is consistent. You can compare the readings with outdoor light in ideal weather in an ideal spot. It is far more accurate than eyeballs or tape measures, though. It can also give you an idea of where you may need supplemental light.

    The following has worked for me, measured from the top of the canopy:
    Starts - 20000 lux
    Veg - 25000 to 35000 lux
    Bloom - 45000 lux (mainly because the colas get close to the lights, not because they need more light)

    Over 100000 can bleach and burn.

    IMG_0229.JPG
     
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  19. you can even get cheap soil moisture meter that read pH as well as have a cheap light meter that works well for reference it was 8$ at home Depot, pH isn't that accurate but the moisture meter is super handy and the light meter is simple but works easily compatible if you bring outside to full sun like previous poster mentioned
     
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  20. That can help you dial in a strain but different strains have surprisingly different tolerances to light. It would be great if there was a light standard in the statistics for a strain along with the yield. Maybe a 1-10 light tolerance meter. Sativa dominant plants can take light that would burn an indica for sure.
     

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