HPS Light Height

M

martymcfly

New Member
I have a 1000watt HPS lighting 18 plants ... right now I have the light 15 inches above the tallest plant ... is that OK, or should I raise it a few inches.

Plants are healthy and my hand doesn't burn after a minute (I have 2 oscillating fans going at full speed) temp is stable at 80F with lights on and 72F with lights off.

These plants grow so fast that I don't want to come home one day to them growing into the light ... so, my question is ... what is the ideal distance for the plants from my light?
 
Hi Missmouse. This lighting chart shows optimal ranges for a variety of sizes of HPS lamp. HPS Lighting Chart - 420 Magazine Photo Gallery

I just lowered my 400 to about 14" today, but I am cautious by nature.

:peace:

edit: This actually might be a better place to get an idea of how close is too close.
 
Since you are using the back of the hand test to feel for heat your plants will not have a problem with the light that close, move the light up as your plants grow.

here are some lumen versus distance charts, they do not take heat into account

Metal_Halide_chart.jpg



HPS_chart.jpg



High_Intensity_Light_Coverage.jpg



grow-room-light-distances.jpg



HPSGraphPAR.jpg
 
Thanks ... looks like I'm OK with the light for now ... my plants are healthy and beautiful, not even a speck on a leaf ... I guess I should go with my instincts on this one. My thumb is pretty green :)
 
JJ Bones said:
Most people are about 18" - 24" away with a 1000w system. I recommend using the back of your forearm not your hand. Back of your forearm tends to be more sensitive so I feel its a better "human" gauge.
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I tried the forearm thing and you are right ... but because I have two fans going at all times, my forearm just gets warm ... I plan on raising the light in a day or 2 though, just to be safe :thanks:
 
at fifteen inches away you are only getting 28k lumens...imo running a 1k light that far away is like throwing dollars out the window.i have never ran an hid light without it being aircooled. prob get flamed but oh well.its almost like you are running a 150w hps by this chart.just MY OPINION
 
tokersmokeg said:
at fifteen inches away you are only getting 28k lumens...imo running a 1k light that far away is like throwing dollars out the window.i have never ran an hid light without it being aircooled. prob get flamed but oh well.its almost like you are running a 150w hps by this chart.just MY OPINION
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Ok, thanks, I'll look into that and put it on my wish list :thanks:
 
Missmouse said:
Ok, thanks, I'll look into that and put it on my wish list :thanks:
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If you've ever gotten a bag of meds and noticed some of the larger colas were discolored or bleached looking its because of the lights being moved too close or the plants being allowed to grow up into them. It's called light bleaching and the higher powered lights like a 1000 watt HPS will do this. The nugs don't have to come into contact with the bulb or reflector for this bleaching to happen.

JJ bones and king john are offering priceless advice in my opinion.
 
Gadfly heat is the issue we are speaking of.its clear she is throwing money out the window.She has 18 plants! at 15 inches away shes killing herself.even with an aircooled hood thats less then 100 watts a piece.Unless shes running the plants defoliated and 12 inches tall they are starving for light even though they look good it could be better.im running 3 600w lights aircooled and get within 6 inches of the plants before bleaching.Life and cannabis is about efficiency and if shes got a light that puts out 140,000 lumens but is only getting 28k shes not even half effecient.Buying mutiple smaller lights is reccomended the 600w is the most effecient.if she was running a 600w light in the optimum range of that chart she would be getting more light then the 1000w 15 inches away.Just my 2 cent 1000w lights produce more heat then light and the needed distance negates running an extra 400w
 
tokersmokeg said:
if you are in an aircooled fixture you can go alot lower i have leaves touch the glass on a 600.
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I have 2 strong oscillating fans going at all times, and the lights are at 14 inches distance with no problems, I'm on limited income right now so I have to made do with what I have ... I think they're looking pretty nice ...

CanopyPicFeb2Resized.jpg
 
tokersmokeg said:
at fifteen inches away you are only getting 28k lumens...imo running a 1k light that far away is like throwing dollars out the window.i have never ran an hid light without it being aircooled. prob get flamed but oh well.its almost like you are running a 150w hps by this chart.just MY OPINION
Click to expand...

I don't have the funds right now, but plan on getting an aircooled fixture soon ... and actually, my electricity bill only went up 20.00 compared to the same time period last year (that's 2 months worth)
 
tokersmokeg said:
Gadfly heat is the issue we are speaking of.its clear she is throwing money out the window.She has 18 plants! at 15 inches away shes killing herself.even with an aircooled hood thats less then 100 watts a piece.Unless shes running the plants defoliated and 12 inches tall they are starving for light even though they look good it could be better.im running 3 600w lights aircooled and get within 6 inches of the plants before bleaching.Life and cannabis is about efficiency and if shes got a light that puts out 140,000 lumens but is only getting 28k shes not even half effecient.Buying mutiple smaller lights is reccomended the 600w is the most effecient.if she was running a 600w light in the optimum range of that chart she would be getting more light then the 1000w 15 inches away.Just my 2 cent 1000w lights produce more heat then light and the needed distance negates running an extra 400w
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Thanks for the info, I am new to this and I was given the 1000watt HPS from a friend. I am trying to keep this as low budget as possible, although I'm not skimping on nutes. If things go well my first time, then I may invest in different equipment. BTW, my electricity bill only went up by 20.00 compared to the same billing period last year (that's 2 months worth)
 
thank you missmouse
100_15393.JPG


i dont have a ruler but this beast yeilded almost 5 ounces when done the light looks mighty close.
100_21782.JPG

this group of plant yielded three quaters of an lb and was a 6o day project collectively harvesting to sustain my needs!!not one plant individualy spent no more then 8 weeks since seeing roots. the light looks mighty close!

so if im wrong i must be the only one doing it.The fun thing about growing is experementation.Dont bash it till you try it type thing.

I usually cut very large clones most of the times the clones are revegged to encourage crazy dense branching.From day 1 i see roots poking out of my rockwool cubes i throw them in amended fox farm ocean forest soil under the 600w hps under the lowest setting 50% for the first two weeks. then full on 600w somewhere beetween 6-8 inches.I do not add any nutes till week2/3 then just botanicare pro bloom and liquid karma.
100_21333.JPG


this is another revegged beast from one of my recent grows.this plant was in veg at the time of the pic and had trichs all over the stem and leaves.this plant yeilded around 6 ounces.i have big plants and small plants running at all times.once the numbers get to high it becomes a chore and security issue, and i like growing monsters.But i never yeild as much as a group of small plants. I read and i experiment sometimes ill try things other people dont.Sometimes i will do an experiment that i think may not work.This is what cannabis cultivation is all about,i started under shop lights with bag seed dirt weed.so missmouse you have a hella start and are years ahead of me on your first grow.cannabis is supposed to be an annual plant,but given the right climate or indoor simulation the plant can be grown and flowered mutiple times,possibly forever.This contradicts everything about the science and classification of plants life span.So until someone tried it they didnt know the possibilities.I think its important for us to get along as not to perpetuate the sterotype many have for cannabis users. missmouse you should start a journal i would follow along. good day to all!
 
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