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the d.o.c

lighting hint

171 posts in this topic

hi gyuys

can someone xeplain these mh/hps lights thing 2 me please cause its all double duch to me sorry are they the same as sodium lights if not what are they and what watt do i need

Metal halide / high pressure sodium

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light intensity virtually doubles every 6 inches closer a HID is to the canopy of bud

light adheres to the "inverse square rule" ,i.e it diminishes to the square of the distance ,which can mean you may be losing a lot of your lights potential ,

always make sure your lights are at the right height to provide maximum lumens but not too close incase of heat and not to far away because it will be less efficient

here is a rough rule of thumb for lights

hang 1000w and 600w HID's 24-36 inches from canopy

hang 400w HID's 18-24 inches from canopy

and smaller HID's to 6-12 inches away

peace :oldtoker:

Also use the hand, iows slowly raise your hand until it feels too hot, if its too hot for you it is for the canopy as well, use this as the clossest you can get w/o burning etc, I also have a oscillating fan blowing between the light and canopy.

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nice, tip. just to add to it; the best practical lighting combination for flowering is generally considered to be a 2:1 ratio of hps:mh.

the mh helps make he buds moe dense and solid than with solely hps lighting.

That's an interesting tip thanks il look into that.

Does the MH produce more blue light or?? I was thinking about getting a 150w blue cfl to go in there as I have read blue encourages trichome production.

What are MH's like for heat? more than a HPS or about the same?

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nice, tip. just to add to it; the best practical lighting combination for flowering is generally considered to be a 2:1 ratio of hps:mh.

the mh helps make he buds moe dense and solid than with solely hps lighting.

That's an interesting tip thanks il look into that.

Does the MH produce more blue light or?? I was thinking about getting a 150w blue cfl to go in there as I have read blue encourages trichome production.

What are MH's like for heat? more than a HPS or about the same?

It's the uv light from the halides that promote the resin production afaik, so the cfl wouldn't cut it.

Halides run a little warmer, my 400 halide gives out about the same as my 600 pure sodium

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i dont know the answer to this so im not being cheeky, but wouldnt more blue than red spectrum light influence just foliage growth? i think the 2- 1 ratio suggested above sounds the right idea.

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i dont know the answer to this so im not being cheeky, but wouldnt more blue than red spectrum light influence just foliage growth? i think the 2- 1 ratio suggested above sounds the right idea.

I think people get too hung up on spectrums personally, both halide and hps are pretty crap in terms of PAR.

Some report more "leafy" growth with the blue fluros or halides, or even the dual specs,but it's negligable imo, especially during the latter 2 weeks of the plant's life as we're discussing here

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