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

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.

I place an oscillating fan pointed towards each of  my lamps(2 lamps 2 fans and this cools the lamp and shade considerably allowing me to get even lower to my plants without burn..............Orinoco

PUTTING FANS IN THERE TO COOL THE LIGHTS IS GOOD BUT LOWERING THE LIGHTS  WILL ALSO CUTT LIGHT SPREAD TO THE REST OF THE SUROUNDING AREA AS WELL TAKE THIS INN MIND IF YOU HAVE A FEW PLANTS IN THE ROOM
                            TOKEIT

Yes D.o.c., absolutely correct.
Also it helps to rotate the plants under the light, both on their own axis and around the growing area. This way every plant gets equal quantities of light throughout its Flowering period.
It is unreal how many grows are "stationary", with plants huddled around the edges and struggling.
With rotation I am happy at 35 watts per sq.ft, well below the suggested 50! I have not noticed any yield deficit however.
Use that light!!!

any objections to me pinning this subject    

I've heard that it's better to use fluorescent rather than incandescent because of it's light giving properties(plants grow better with fluorescent). Is it true? and if so, what about halogen? Where does it fall?

Halogen falls down the pan....absolutely useless for plant growing purposes.......

Flouros okay for small plants in veg and rooting cuttings.....

HPS/MH you need for growiung anything really worth smoking.....

Mono....x

Yes, halogen do not have the right light spectrum for growing.

A friend of mine places a piece of wood along the length of both walls and then a piece of wood accross the growing area - this is where he places his lights. This means that during the day he just slides the piece of wood along the wall #(the two pieces of wood along the wall act as rails) and it acts as a cheap light mover..I will be doing this and will make a thread of it - after checking that it has not already been done.

So how does the MH / HPS thing work... Do you use MH for vegging and HPS for flowering?
A combo?

Thanks!

I've gone vertical. Got addicted to the "Vertical Limits" forum at CW. Then latched on to krusty in the hydro forum before his treatment of trolls made him unwelcome. (Site is down at present.)
Trouble is, Ddocs systems are for commercial growers not scared of high plant numbers, and krustys' freedom buckets need a noisy compressor and 10 Kw of lighting. A bit too rich for me, I'm just a personal guy.
I've removed the reflector, (400w HPS) and suspended the bulb from the ceiling. Now the plants form a circle around it. Room for maybe 12, but I was cloning for the old space and have only 7.
They're growing better, temps are lower, and some fan leaves at the back are bolt upright catching light. Looks cute. Up to now, (3 weeks of flower,) they've set their own limits of how close they should get to the bulb. Looks like a large green bowl.
I'm not the most attentive of gowers, and it'll take a few crops to sort a new easy-grow regime for them, but looks good so far.

can anyone help me out here...my m8 seems to think that using an energy efficiency light bulb(as used by rizlaman and cuban pete-both have sexy plants on the go )
aren't very good, i however, would like to purchase some as they seem to have worked before for others and they seem very cheap for a first timer with only a couple of plants.
cheers

Sod your mate rudeboy

You've seen the results that are possible with compact flouros.

give it a go and when you harvest your first bud don't let him smoke none. (only kidding)

Even if you only get a small amount of airbud on the first attempt it's better than no bud at all.

Once you've got a couple of grows under your belt you could either up the lighting or learn about and try scrog (SCreen Of Green) growing to increase your yeild.

Go for it m8

npk

strider id love to see some photos of that man, dont think theres any verticle grow pics here yet...?

QUOTE (NPK @ Jun 16 2003, 06:23 PM)

Sod your mate rudeboy You've seen the results that are possible with compact flouros. give it a go and when you harvest your first bud don't let him smoke none. (only kidding) Even if you only get a small amount of airbud on the first attempt it's better than no bud at all. Once you've got a couple of grows under your belt you could either up the lighting or learn about and try scrog (SCreen Of Green) growing to increase your yeild. Go for it m8 npk

sweet m8, my m8 isnt too happy wiv ur post, altho im more convinced an he now reckosn we'll get less green! honestly some people ey hehe

well im tryin it an im growin teh stuff round my place so he cant really do much about it!!!
at the moment its on the window cil
anyways, best shoot, got a philosophy exam 2mrw morning an im dreading it
cheers

I'll try for some pics. Damn camera eats batteries, but it's payday soon. Don't expect anything brilliant, it's just 7 kitchen bins connected to a big air pump.

Confused,
Just read the post re hight of the lamp, does this also go for the seedlings?
All my seedlings have about 4 inches before any real vegitation, and they look nothing like all the pics you see on other sites.
With my grow room only having a small headspace, I was looking to produce small bushy plants, any tips on how I could manage this.

Fly high
Phroggy

slightly off this topic although electricity related:

my mate has a little water heater thing in his kitchen that stays on when he turns his electric off...!!! he has no idea where the supply comes from.... when he told me this my immediate though was probably the same as yours...: run the lights off it! - thing is how would he splice the wire or what ever when he cant actually turn off the supply to the thing....

???

has he tried pulling the company fuse (the big bugger before the meter and fuse board)?
There arnt any street lamps on the side of his house by any chance?

High!

So if I have a 5 foot by 2 foot by 8.5 foot(height) growing space I am going to need 2 400 watt HPS and 2 175 watt MH?!?!?!? I want to use some combination of MH and HPS. Currently I have 1 400w HPS and 1 400w MH in this area. The heat from the MH is a potential issue, ranging from 76 to 84 F.

I currently own:
1 switchable 400 watt ballast running as HPS
1 400 watt MH
1 175 watt MH

I only plan on growing to 3 foot maximum

suggestions are welcome thanks for any help

Stealing electricity is one of the best and most efficient ways to.............

...get busted

*ahem* Eastenders *ahem* Martin *ahem*

, that whole storyline makes me larf! i even watched a few episodes!! gettin busted is everyone's biggest worry... a good friend of mine got the dreaded knock (well, fone call from polis who had already arrested his g/f) he claimed stupidity, no kidding... there were only 4 of em and 3 weeks into veg.. i did feel bad as i gave him the cuttings... but.. result: a CAUTION, being *somethinged* made null or whatever after one year, and only in derbyshire!
on a relevant note: after a successful outdoor grow this yr (low yield but gooood stuff!) i'm thinkin of movin indoors, so... a) where's the best place to get lights from? i've seen a grow in super limited space, utilising the idea of uplighting as well as OH lights... this makes sense to me and would theoretically make max use of the space... what does anyone reckon?

what about enviros? does the same 'losing half intensity per 6inches" rule still apply? Ive got my plants about 6 inches away from my enviro. Only small plants mind, 3 inches tall.

absolutely, its simple physics! - you can get your plants incredibly close to an enviro - an inch or two is fine!
It isn't actually the six inch rule, its properly called the inverse square law - as light spreads in all directions, if you double the difference between the light and the plant, the plant receives a quarter of the light!
ie if you have 50w sq ft at 5 feet, at ten feet, it would be 12.5wsq ft

omg! *runs home to lower my enviro*

if I could find the rest of my damn batteries I could photograph my grow..
5 weeks into flower with 2-400 watt MH.
got a great deal on the lights 2 with bulbs, brand new for $50.(in U.S. by the way)
probably change 1 to an HPS conversion soon. But my point is.. I'm a first timer mind you, but these buds look fantastic.
Maybe I'll just do the next grow with an added HPS to see the difference for myself.
I so badly want an opinion on these... aaaargh!

if using an hps, you have to leave a fairly hefty distance between the bulb and plants - I was reading an advert for a company that does "winged" reflectors, and the light guards that go underneath the bulbs - having looked at their ray drawings, they do indeed look like a damned good idea - you can effectively halve the "airgap" using this system ,which should make light distribution a lot more even, and you've increased the amount of light hitting the plants a hell of a lot...............the question is, have users of these lights found that their claims are born out in practice?

I know the company you're referring to when you mention (hold on let me just adjust-a me seat ) the ray drawings, I don't know if the claims they make on their reflectors are true, but what I do know as I use one, is that the heat shields that they advocate to use with them certainly do

presumably you can get the plants closer too! - this is one of the things that put me right off hps for cupboard growing - apart from the heat, it's the fact they rob you of a lot of headroom when its limited!

I can grow plants alot closer with the shield in place. I estimate with me 250 that I can get them within 8-10cm (3"-4").

Don't flame me Vlad I know me setup ain't as it should be, but with running the intake just below the shield, it allows me to maximise me headroom

At the moment I'm just sticking with the enviro until it gets real chilly outside, (alright I'll admit that I do run the HPS now and then) then I'll wack 'em both on and still maintain that 75F ish.

-no worries mate! - it just looks like a very intelligent way of "equalising" the light as far as possible.......may even work with enviros! (except you wouldn't need the heat shield) - I've often looked at conventional reflectors, and reckoned they were pretty lacking, but the diagrams produced by the "wings" company further confirmed it - the craftiest bit as far as I'm concerned is the "widows peak" in the centre - all the other reflectors will just chuck all the light in the centre straight back into the bulb. where it'll do no good at all...............

One thing I must say is the way the heat shield's are advertised you would almost think that it extracted heat from the GR too

The way they work is by pushing the heat that is created by the lamp back towards the reflector, and also out to the sides.

In my GR it just has the effect of keeping the heat at the very top (oh when will he get a fecking extractor ) of the cupboard and away from the plants. If I didn't use it then the heat would reach alot further down and therefore make the environment a lot warmer and dryer. Without it I was struggling to maintain humidity above 25%

As the intake runs below this it sort of creates a two tier system, with the hot air at the top and then the cooler CO2 laden air running below this but at the top of the canopy

Like I said, it ain't exactly ideal, and I wouldn't advocate anyone growing like this, but hey, it works for me...

Imagine the results I could achieve with an extraction fan

Do u get any maunfacturers performance figures when you buy these lights?

specifically envirolights - average temperature of the bulb when running 18/6?

wow thats all clever stuff, generally speaking you should be able to hold your hand level with the canopy under the light for about a minute with out it burning if it does raise the light etc etc

Hey i have a question concerning lighting if i used 3 compact fluorescents do u htink id be ok for my grow or should i stick with HPS

Stick with the HPS

, but what I do know as I use one, is that the heat shields that they advocate to use with them certainly do :yep i use a heat shield also . am impressed! no more lanky seedlings

There are of course those air cooled lamps which you connect to a RVK 125. I would imagine that you could get your lamp closer than usual using one and therefore increase it's effiency. However, there not cheap.

Has any one used one? Do you recommend them?

build one. well easy. cheap too.

Been using the same systen for a while now myself [attachmentid=45159]

works a treat

i use flouros for seeds & cutts, M.H for 2 weeks of veg & H.P.S for 8 weeks of flower.

i primarily use fullspec hps ands suppliment it with strategically placeds flos.
fullspec hps saves messing around (and avoiding the expence)

im thinking about supplementing my 400w HPS flowering room wit some blue enviros. ive read somewhere that a bit of blue light make the buds well compact. can any1 vouch for this?

dont really want to spend £50 on two 125w enviros if it wont do much

peace

I tried this but the radiant heat still frazzled the top leaves although the air temperature was OK. Lucky I noticed in time to move the light back up a bit

I hang my 600W hps less than a foot away from my plants with only an oscillating fan for ventilation. But I have one of those heat shields under the bulb.

Hiya Pinhead,for all types of lighting the inverse square law applies. Forget about 'losing half intensity per 6inches'.

The rule is,in laymans terms is that if you have a light emitting say 10,000 lumens at a distance of 2 feet and you double the distance to 4 feet,you will have 2,500 lumens of available light.

If you halve the distance to 1 foot,you will have 40,000 lumens of available light.

Simple,innit?

Flours Grow Great Buds, Far worth of smoking, and eazy 400.00 a zip shit, my buddy harvested a QP off 1 flour plant, and it was some of the best smoke i've had, So fucking sticky eeky, and buds the size of 12oz soda can.

im oretty sure halogens r not any good for growing as they lack the blue spectrum and half the red stectrum of a fluro