Lighting Information For Anyone Who Wants It

Hubert

Well-Known Member
I felt inspired tonight :joint: So I wrote a little overview on lights, mainly for the clueless as current growers are probably well aware of the different lights out there. I hope this helps someone out, I feel somewhat indebted to the growing community....

I often hear/read the question, 'What kind of lights should I get for my growroom'? It's a question that's hard to answer, there are alot of variables in the equation so to speak. It really depends on your grow style, your space, your temps, and personal preferance. Some growers just prefer certain lights because they have experience with them, or they best suit their needs. So before you ask that question consider all the things that may help make the decision for you, your space, temps, and style.

The best lights you can get are, without much argument HIDs, or High Intensity Disharge lights, these include Metal Hallide and High Pressure Sodium among others. These lights have unrivaled intensity and penetration, but they do have they're drawbacks. HIDs are infamous for the huge amounts of heat they generate, which can quickly overheat a growroom if not properly ventilated or cooled. The difference between the two comes down to spectrum, the colour of the light being emitted. Metal Hallide or MH is commonly used as a vegetative light, the blue-ish spectrum promotes fast vegetative growth by mimicking a summer's day. High Pressure Sodium, or HPS is at the other end...flowering, with a much more red-ish glow HPS simulates an autumn's day, the plant's natural flowering season.

Next in line are fluorescents, but these are also split into their own groups and have their own uses. Generally speaking the best of the fluoros are HO T5s which mean High Output, T5 is just the model of bulb. There are also T8s and T12s, neither of which have much penetrating power but certainly hold their place in the veg or clone room. They can also be used fo flowering under the right conditions. Fluoros have the advantage of being able to stay relatively close to the plants, therefor allowing for maximized coverage. Amazing results have been acheived with fluorescent bulbs, a testament to the grower's ingenuity.

Compact Fluorescents, or CFLs...I mention these seperate as they are a little different than regular fluoros in use. CFLs for example screw into any regular light socket, there is no need for ballasts or big fixtures. They are very cheap in comparison, you could easily get 400w of CFLs for under $150, but they to have they're drawbacks. These have the least intensity/penetration of the three mentioned light types, and often don't have spectrums ideal for plant growth. However, there are bulbs out there that can be used for veg and flower, you just have to know what you're looking for.

LEDs are the up-and-comers to the grow world, but they are insanely expensive for what they are at this point...no more discussion on this until it becomes a relevent topic.


Please feel free to ask anything more specific, I just didn't want to type forever :mrgreen:
 

highdro

Active Member
Hubert,thanks 4 the info.I got a spot 3ftx1.5ft im using flouresents do you know about how many watts I should be using.im tryin to make a place 2 clone and veg do I need to line the whole thing with flourecents?
 

Mr Green Man

Well-Known Member
What about the large, high watt CFLs, specificly made for growing?

I have a 125Watt one at the moment that I am using for a mouther plant. They also make a 200Watt, and they come in Blue and Red Spectrums.

These are cheaper than buying multiball small bulbs
I think that it is a good light for small grows, Clones, early Veg, Seeds and mothers.

That said I wouldn't dream of trading in My HIDs.
 

Hubert

Well-Known Member
Hubert,thanks 4 the info.I got a spot 3ftx1.5ft im using flouresents do you know about how many watts I should be using.im tryin to make a place 2 clone and veg do I need to line the whole thing with flourecents?
Good question highdro, I meant to include a few things I forgot about...

Generally speaking most growers go by watts per square foot when it comes to determining the amount of lighting you need. Alot of people I'm sure have varying opinions of minimal lighting, so keep that in mind...they are opinions, the more the better generally though. IMO Good vegetative growth can be achieved with with about 25w/sq ft. like I say though more is better. Flowering on the other hand is usually recomended at 50w/sq ft. min. I've flowered with less light than that and had fine results, but I've also flowered with more light and had better results.

To answer your specific questions though...your space by my calculations is about 4.5 square feet. Add in anywhere from 25w/sq ft and up...so about 125w would be a good starting point, but again...the more the better.



What about the large, high watt CFLs, specificly made for growing?

I have a 125Watt one at the moment that I am using for a mouther plant. They also make a 200Watt, and they come in Blue and Red Spectrums.

These are cheaper than buying multiball small bulbs
I think that it is a good light for small grows, Clones, early Veg, Seeds and mothers.

That said I wouldn't dream of trading in My HIDs.
That is a good point, alot of CFLs and regular fluorescents are quickly gaining ground in the grow world. The only drawback to the bigger CFLs is that the heat is also more concentrated along with the light. They seem better as a main light source than they do sidelighting, the smaller cfls run cooler and can be kept a little closer...good for sidelighting.
 

jaiddragon

Well-Known Member
Hi yall, I am very new here and found this forum while looking for information on LED lights for growrooms. I've only attempted one grow years ago that was ended by a vicious case of spider mites, and have just recently gotten back the required privacy to try again. I tried searching the forum for the info but didn't find what I was looking for. (It's probably right in front of my face but I'm too stoned to comprehend what I'm seeing)

I read in the first post that LEDs are very new and considered expensive to get...

I found some on ebay in panels or floodlight type bulbs and the prices are a bit high but from what I have seen of HPS and MH they are a bit pricey too.

led grow light, Yard, Garden Outdoor Living, Inside the Home items on eBay.com

I have been looking around this forum as well as the internet for more information from people that have used these lights as opposed to the manufacturers information, which, of course, tells you that these lights are the best thing since sliced bread. :roll:

I like them mainly for the extremely low power usage and heat output, and for that reason would be more than willing to pay more for them.

My questions are these:

For a very small grow, say 1-4 plants, how many of these panels/bulbs would I need? Reference the ebay page if you could because this is probably where I'll buy them, unless you have a better idea.

Should I buy seperate red and blue panels/bulbs or are the mixed ones good to use for vegatative and flowering?

The info says you can pretty much put them right up on the plants without fear of burning or overheating, will any other problems develop from doing this?

Thanks for any info that you have, I know I'm forgetting something but it will probably come to me later when I'm miles away from the comp lol.

The more research I do, the more discouraged I'm getting about the LEDs... just found this 400w MH on ebay NEW 400 watt METAL HALIDE GROW LIGHT w 400w MH LAMP hps - eBay (item 180230057133 end time Apr-20-08 12:03:00 PDT)
does this look like a good deal to you?

I'm satisfied that this will be enough light for my plants but I'm worried about power consumption and heat, hence my desperate want of the LEDS lol, I'll have to do one of the calculators to see what it will turn out to be. Really just interested in seeing any opinion on this particular MH fixture if no promising LED info is forthcoming. Space will be a closet roughly 6'x7'x2'. Also, the doors are fully mirrored on the outside, if I could hang them mirror side in would that be a good reflector? or would it focus the light in hot spots and burn something? Sorry I'm rambling, that's what I do....
 

Mr Green Man

Well-Known Member
Hi,

Mirrior isn't the best reflector. Flat white Paint is probabaly the easyest/ccheapest and also one of the best.

LEDs, well I have done a little research, some one did a grow jerunal using them, have a look for it. So far, I am not impressed.

I think your space is a little too long for a single 400, I think 3 to 4 Feet (Depending on your reflector is going to be the max. But hey do't for get you will need some space for a Fan and proabably a DE humidifier and some other shit. so could work out good for you.

Personly I would go with the HID 400, although I would try and get an HPS for flowering. As a second I would get maybe 3 200W CFLs but that would work out more $ in the end, and probabably wouldn't be as good.


w/sq ft

Thats fine but not all light is equel.
HPS is twice as efficent as say CFLs, so 25w/sq ft of HPS is = to 50w/sq ft of CFL

Would you agree?
 

massbaster

Well-Known Member
Good question highdro, I meant to include a few things I forgot about...

Generally speaking most growers go by watts per square foot when it comes to determining the amount of lighting you need. Alot of people I'm sure have varying opinions of minimal lighting, so keep that in mind...they are opinions, the more the better generally though. IMO Good vegetative growth can be achieved with with about 25w/sq ft. like I say though more is better. Flowering on the other hand is usually recomended at 50w/sq ft. min. I've flowered with less light than that and had fine results, but I've also flowered with more light and had better results.

To answer your specific questions though...your space by my calculations is about 4.5 square feet. Add in anywhere from 25w/sq ft and up...so about 125w would be a good starting point, but again...the more the better.





That is a good point, alot of CFLs and regular fluorescents are quickly gaining ground in the grow world. The only drawback to the bigger CFLs is that the heat is also more concentrated along with the light. They seem better as a main light source than they do sidelighting, the smaller cfls run cooler and can be kept a little closer...good for sidelighting.

when i do a search on lighting, most people are talking in square ft? BUT when we are talking grow spaces we deal with cubic ft.

my grow space is approx. 3ft wide 3.5ft high and 2 ft deep.

my box is 3-d and i live in 3-d but i light in 2-d?

hmmmm.....:confused::spew:
 

Auzzie07

Well-Known Member
He's right. But it's still good info. Every time the phrase square ft is used here, just mentally change it to cubic ft.
 

jaiddragon

Well-Known Member
Ok, think I've come to terms with the fact that MH and HPS are the way to go after talking to my personal guru..(who has grown the best herb I've ever smoked, ever)...

Found this system that's switchable and comes with both bulbs NEW 400 watt switchable HPS + MH GROW LIGHT hood system - eBay (item 160226253556 end time Apr-21-08 12:00:00 PDT)

This seems like a great deal to me but is there something I'm missing? Some other component that's needed?

Thanks for the answers y'all, I appreciate it.
 

Audone

Active Member
I ordered my 400w remote digital ballast system from HTG supply. Totally happy with it. I don't see why so many people go with cfls. THe HID is soooo much better and really not that expensive.

It looks to me like that system you are looking at would be alright. Id have to look at the picture closer to see if the vents could be hooked up to ventilaton ducting. That is one drawback is the heat but that is why I have my light vented seperately from the grow area so there are no smell/filtering issues.
 

Hubert

Well-Known Member
HPS is twice as efficent as say CFLs, so 25w/sq ft of HPS is = to 50w/sq ft of CFL

Would you agree?
Not neccessarily, CFLs can be kept much closer. Your question ties into this next question.....


when i do a search on lighting, most people are talking in square ft? BUT when we are talking grow spaces we deal with cubic ft.

my grow space is approx. 3ft wide 3.5ft high and 2 ft deep.

my box is 3-d and i live in 3-d but i light in 2-d?

hmmmm.....:confused::spew:
Very good point, I often find myself arguing that very thing. Watts per square foot only applies to SOG grows, with an even canopy the light can be distributed evenly. So...watts per cubic foot and watts per square foot could only be the same in an even-canopy grow (with the light 1 foot above the canopy). This is where fluorecents come in really handy, you can keep them alot closer thus increasing your watts/cubic foot. That's why I mention them as great sidelighting, you can even out your light distribution and so even out your growth. With an overhead light you'd be at dismal light levels near the bottom of an untrained plant, with CFLs you could have even lighting over the entire plant.


This seems like a great deal to me but is there something I'm missing? Some other component that's needed?

Thanks for the answers y'all, I appreciate it.
Switchable ballasts are fine, they can save you a bit of money rather than buying two....but the drawback is that you can only have one cycle running at a time, you can either veg or flower, not both.
 

Shook

Well-Known Member
i can get LED's for free :) mind you i can only take a few at a time, but, im thinking about making my own led board
 

Hubert

Well-Known Member
Okay there seems to be alot of confusion going around as to how one decides what specific bulb they want/need. I read threads about lumens, watts, and kelvins...so let's get this all straightened out :mrgreen:

Lumens - The lumen (symbol: lm) is the SI unit of luminous flux, a measure of the perceived power of light. Luminous flux differs from radiant flux, the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light.
I think that is fairly self-explanitory.


Watts - The watt (symbol: W) is the SI derived unit of power, equal to one joule of energy per second.
Nothing more than an amount of energy your lights give off...including heat.


Kelvins - The kelvin (symbol: K) is a unit increment of temperature and is one of the seven SI base units. The Kelvin scale is a thermodynamic (absolute) temperature scale where absolute zero, the theoretical absence of all thermal energy, is zero (0 K).
What this means is that Kelvin ratings apply only to an ideal black box, this system was far more accurate in the days of incandescents. HIDs and Fluoros however do not maintain a consistent temperature, they spike in temp...and therefore would spike the K ratings. The Kelvin rating given on the package is nothing more than an average output, the same average output could be acheived with a variety of spectrums. (I have graphs to show this fact if anyone would like to see)


None of those terms are useful. They do not provide enough information to base decision upon. The only way to accurately use of them would be to have a standardized system where (X)Watts would be equal to (Y)Lumens, and (Z)Kelvins. That is not the case however, bulbs A, and B may have the same amount of Watts, and a very different amount of Lumens. They could also have the same amount of Lumens and very, very different Kelvin ratings.

Now that being said, I don't mean to say we have to stop using these terms...I just think alot of people are putting too much emphasis on them.

*All quotes from Wikipedia
 

nickfury510

Well-Known Member
watts is the amount of energy the light uses to produce the specified kelvins and lumens.......

A watt is a measurement of total electrical power. Volts x amps = watts.
Bulbs come in various wattage ratings. This describes how much electrical power a bulb uses and does not describe how bright it is. Different bulb technologies will produce differing amounts of light per watt. A fluorescent bulb is 4x as bright as the same wattage incandescent bulb. ...
aquaticconcepts.thekrib.com/Lights/
 

Hubert

Well-Known Member
watts is the amount of energy the light uses to produce the specified kelvins and lumens.......

A watt is a measurement of total electrical power. Volts x amps = watts.
Bulbs come in various wattage ratings. This describes how much electrical power a bulb uses and does not describe how bright it is. Different bulb technologies will produce differing amounts of light per watt. A fluorescent bulb is 4x as bright as the same wattage incandescent bulb. ...
aquaticconcepts.thekrib.com/Lights/
Yes...I agree. Watts also takes into account whatever energy is being lost to heat.
 

Hubert

Well-Known Member
I'm satisfied that this will be enough light for my plants but I'm worried about power consumption and heat, hence my desperate want of the LEDS lol, I'll have to do one of the calculators to see what it will turn out to be. Really just interested in seeing any opinion on this particular MH fixture if no promising LED info is forthcoming. Space will be a closet roughly 6'x7'x2'. Also, the doors are fully mirrored on the outside, if I could hang them mirror side in would that be a good reflector? or would it focus the light in hot spots and burn something? Sorry I'm rambling, that's what I do....
The LEDs I've seen for a reasonable price didn't have very impressive results compared to HID lighting. It is also hard to find ideal spectrums in LED, there are alot out there but the problem with LEDs is that they use a different elements to create each different colour. And it seems (coincidence?) that ideal growth spectrums cost a bit of money to make, the elements needed are apparently what's holding LEDs back. The price will surely fall with time.
 
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