Why can't you used 4100K bulbs?

Shredder111

Well-Known Member
Why aren't 4100K bulbs useful to your plants? Isn't this bulb a mix of color between 2700K and 6400K? Maybe it is dependant upon which spectrum the plant can absorb, no?

Thanks much:weed:
 

Roseman

Elite Rolling Society
Plants love the early Spring rays of the sun for growing tall. They are uba rays, and duplicated in High Kelvin lumens or around 6500 Kelvins for the Vegging Cycle..

As the summer rolls around, and toward the end of July, the sun's rays emit more uvb rays, low kevin rays, duplicated in 2700 kevin lights for their Blooming cycle.

That is what plants want and need at certain times.

A mid-range k bulb, like the 4100 and 5100 are helpful and useful, but not as helpful or useful as the high and low kevin bulbs at certain times.

There, I think that explains why correctly. Someone will surely correct me if I am wrong.
 

Nocturn3

Well-Known Member
I couldn't find a cannabis-specific chart, but it is similar to this:



The 4100k bulbs are somewhere in the middle of this scale, and are therefore not absorbed as efficiently as blue or red spectrums (which, if I recall correctly, are processed by two seperate chlorophyll types).
 

Roseman

Elite Rolling Society
Study this:

42 watt average $10.00 each

65 watts, = $23.99 average price

85 Watt, average $29.00 each




105 watt average $38.99 each




Or Look for Clamp Reflectors and Bulbs together:




CFLs come in 15, 26, 42, 65, 85 and 105 watts.
The 26s and smaller are like big breasts on a nun, and not good for anything.

26s to 85s do not put out any noticable heat. The 105s put out some heat, but not as much as HID lights.
The 42's are about $9 each.
65 watts are abut $24 to $25 each, 85s are $30 each, 105s are $39 to $42 each, average is $40 each for 105s.
a CFL needs a reflector, like a hood. I like the $10 heavy duty clamp reflectors at Lowes, Home Depot or Walmart. They also offer a cheaper $8 reflector but it is smaller and flimsey.

With CFLs, you need the DUAL SPECTRUM, red and blue. That does not refer to the color of the bulb that you see. It refers to the kind of rays, UVA or UVB, or the color temp, called kevins.
CFLS come in 2700 kevins, 3000, 4100, 5100, and 6500.
2700k is for BLOOM OR FLOWERING , 6500k is the VEG Spectrum. The others are "MID" spectrums or in between.
In outdoors, the sun produces different rays in the spring (VEG Rays called Blue) and late summer for Bloom spectrum, the RED spectrum. (see more below)

CFLs are new on the scene, in 2006 the biggest made was 65 watts. When we talk about CFL watts, we are talking about the actually electricity used, NOT the equivalant. For example, a 15 watt CFL bulb puts out 60 watts.

CLFS PUT OUT LIGHT FROM THE SIDES, NOT THE ENDS OR TIPS.

YOU CAN GET SPIRAL CFLS (15, 26, 42, 65, 85) AND TUBE TYPE CFLS 105s.

this is from a magazine artice I wrote and a newsletter I wrote for Stealth Hydro:
How much light is needed for growing?
Depends on the size of plant you are trying to grow. I'll try to answer this "in general" instead of being specific to one size plant. Light seen and perceived with the human eye is measured in Lumens. There is an ideal amount of lumens for growing and a minimum amount of required lumens. The very minimum amount of light required for smaller sized plants grown is around 3000 lumens per square foot. Let me put emphasis on "minimum amount" of light. However, that's not 100% exactly accurate, since although you may have a 10,000 lumen light, the amount of light that reaches the plant varies with the distance between the light and plants, and the reflectivity of the grow area. The ideal amount is somewhere around 7000-10,000 lumens per square foot for average sized plants. As long as the plants do not show burn, as much light can be used as you want to use. (Note, the sun produces about 10,000 lumens per square foot, on a sunny mid summer day).

Determining lumens for your grow area:
First determine the square footage of your area (example in a 4 foot by 4 foot area, there is 16 square feet, 2 by 2 feet is 4 Sq ft. ) If you have a 1000 Watt High Pressure Sodium Light Bulb, that produces approximately 107,000 lumens. Divide this by 16 (your square footage) 107,000 divided by 16 = 6687 lumens per square foot. So just divide the total amount of Lumens, by the total amount of square feet, and that's your lumens per square foot.

How far away from my plants do the lights go?
The lights in your grow room should be as close as possible to the plants without burning them. There is no such thing as too much light, unless there is overly sufficient heat to dry out and burn the leaves. A good rule is to put your hand under the light, if its too hot for your hand, chances are that the plants will be too hot too, so move the light up until your hand feels more comfortable. For seedlings or sprouts, I keep them a little further away from the light, because they are very susceptible to burning and drying out, at these young stages.

How do I decide which lights to use?
Efficiency is very important when choosing a type of light. The wattage is not the most important thing, different types of light produce different amounts of lumens per watt. For example, a 300 watt incandescent will produce about 5100 lumens. (not that you can grow with incandescent bulbs) While a 300 watt Metal Halide (just an example, they do not come in 300 watts), will produce 27,000 lumens. Obviously far more efficient for growing, while still using the same amount of electricity.

Approximate light production:
Incandescents: 17 lumens/watt
Mercury vapor: 45-50 lumens/watt
Fluorescents: 60-70 lumens/watt
Metal halide: 90 lumens/watt
High pressure sodium: 107 lumens/watt


Incandescent lights: Incandescent bulbs are the most popular type of lights in the world. They may come advertised as incandescent, tungsten, quartz, halogen, or simply standard. The important thing about incandescent bulbs when it come to growing is simply this: they suck. Using incandescent bulbs to grow plants is like trying to flag down the Space Challenger with a burnt out match! You can do it, but it won't work. There are some incandescents which are sold as "grow lights." They usually have a blue coating and usually come in 60W and 120W sizes. While they may seem like a good choice to new growers, they are next to useless; they produce some light at a usable spectrum, but only have about a 5% efficiency and generate more heat than usable light. Most of us have these in our homes right now. Don't use them for growing, instead opt for a Compact Fluorescent, CFL, as a cheaper but more efficient alternative.

Fluorescent lights: Fluorescents are far more useful than incandescents. They are efficient enough, and much less expensive than HID (High Intensity Discharge) lights. Compact fluorescent tubes, (commonly called CFLs) are popular with growers because of their good output to size ratio. Compared to standard 4 foot tubes, CFLs are smaller, more easily moved, and more can fit into a given small area. CFLs are good for small grows on a tight budget, and for novice growers, since they do not require any special sort of wiring or understanding of the necessary bulbs for a given fixture, and the small wattage ones (23, 42 and 65) are very widely available. Fluorescent lights come in many different Kelvin (spectrum or color) ratings; often the spectrums are labeled on packaging as being 'cool white' or 'warm white.' Cool white is more blue, and is good for the vegetative stages of growth. The bulbs are ultra white. Warm white light is more reddish in spectrum, and is best for the flowering stage. The bulbs are almost cream colored.

Color rating - Measured in Kelvin (K). The higher the number, the more bluish the light. 4000K-7000K is mostly on the blue side of the spectrum for Vegging or GROWING, while 3000K and under goes from a white spectrum, to a redder spectrum and is best for BLOOMING or FLOWERING.


High Intensity Discharge (HID) Lighting Systems:

Mercury Vapor (MV)
Mercury vapor lights are not the most efficient light for growing. They are very bright, and relatively cheap. They do emit light at the wavelengths necessary to support your plants growth, but not nearly as good as a MH or HPS light. Much of the light emitted by MV lights is bluish-white. Street lighting is what most MV lighting is used for.

Metal Halide (MH)
Metal halide lighting systems are optimal for use in the vegetative phase of growing. They emit mostly blue light, which encourages vigorous growth of foliage. They are very efficient, but can get rather expensive to start with; fluorescents may seem more appealing because of their lower price, and they are not much different when compared on a lumen-to-lumen cost level. These lights can be used through-out the grow, but leave a lot to be desired in the BLOOM stage.

High Pressure Sodium (HPS)
High pressure sodium lights emit mostly orange, yellow, and red spectrum light, which is perfect for the flowering stage of the plants growth. They are (in my opinion) the most efficient type of light available for any application if you are not on a budget and can vent the grow area for heat. HPS lights can be used through-out the entire grow. They produce more dense and usually larger flowers or fruit than any other light. HPS lights are generally a little more expensive than MH systems of similar wattage. They are more commonly used by experienced commercial growers because of their ability to produce tighter denser flowers, higher lumen-output-per-watt, and will produce from start to finish.

Just like everything else, available grow lights are evolving. Remember how the sun produces 10,000 lumens per square foot in the mid-summer. Well, today there are CFLs that can actually duplicate those lumens. If you can not grow under the sun, then bring the sun inside. Yes, you can have 20,000 lumens covering the entire grow space with the new 105 watt per bulb CFLs. Three of these bulbs in the proper reflector actually yields 20,000 lumens.This is what I get with my CFLS:



am very happy with 4 65s,a dn 4 85s, vERY HAPPY, adn the additional 105s are great, but I have to keep a fan running and I am not as STEALTHY as I used to be.

Dual Spectrum 65 High Output Fluorescent BulbsLow heat, energy efficient light bulbs for use with Stealth Hydro Dual Spectrum Lighting Systems. Available in blue (vegetative) and red (flowering) spectrums.


65s are 23.99 each.



Price: $23.99 Dual Spectrum II High Output Fluorescent BulbsLow heat, energy efficient light bulbs for use with Stealth Hydro Dual Spectrum II Lighting Systems. Available in blue (vegetative) and red (flowering)
spectrums.



85s are 29.99 each
Multi Spectrum Fluorescent Tube CFLLow heat, energy efficient light bulbs for use with Stealth Hydro Multi Spectrum Lighting Systems. Available in 6500 K (vegetative) and 3000 K (flowering) spectrums.
Price: $38.99



And $9 each for the 42s.

The pics do not show the 42s that I put on the sides, on a STAND I made from a metal shelf.

I like being able to move the CFLS around, adn lower them down in between the plants, the clamp- reflectors are just $10 each.Lowes, Walmart, Home Depot:





then one of these:


and if you want to add two lights to a reflector, you get a Y spliter.
 
yeah so 4100 k represents the temperature of a black body with the same peak in spectrum. for 4100, that peak is really close to green, which is not used by plants for photosynthesis. Mixing warm and cool bulbs is a good idea, using something in between is a very bad idea.
 

Kevin A

Active Member
Great Thread!!!!

What is a good ratio of 6500k to 2700k for flowering. I have about 6 2700's and 3 6500's I also have a 85w*2700 and the rest of my 27's are 15w while my 65's are 26w.

I have 4 plants.

Only have one reflector for my big light. The rest are bare bulbs hanging from y-sockets

Sorry for invading this thread with this question.
 

saintgraff

Member
I'm using some 4100k 45watt bulbs and it's working perfect for me im actually surprised how well my grow turned out
 

Sativus

Active Member
I have been growing now for about 18 months in my grow box. I was using the 48 inch T8's at the 4100K temp (10 of them custom fitted to my 16 inch wide x 48 inch long box). The plants grew seemingly fine in my novice opinion. After seeing the color chart mentioned earlier, and I believe I saw the marijuana specific one too elsewhere, I was shocked. I like many others thought the 4100K bulbs would be a happy medium in the K ranges for veg and flower. That is simply not the case. I now have 6500K tubes in my box and am looking forward to increased growth in veg. If these charts are correct, the plants should simply love the change in lights and it should be very noticable.
I also got me a 400watt HPS for my flower box. I am hoping for a better return from the HPS in the 2100K pushing 50000 lumens then I was getting from the 320watts of 4100K tubes pushing 27500 lumens I last flowered with... I am almost gitty I am so excited ;)

So the plants can grow with the 4100K lights, but the plants would seemingly MUCH rather lights in the high K range for veg, and the low k range for flower.
 

droach18

Member
I bought and used 4100k bulbs for vegging and as a combo with flowering and I have not noticed any issues whatsoever. I keep reading all over the place that they are no good but I think it's a common misconception. Also I have read that alot of MH light bulbs operate at 4100k and those have been used for a long time with the best results so I could see no reason why they would not work. My plants have grown just as fast and as healthy with 4100k bulbs as 6500k, so ya I dno.
 

FATBOYFRESH

Well-Known Member
Im about fo grow with 6500 &4100k in tandem because if you use weins law and divide the max absorbtion of nnm in chlorophyll A&B of 660&440 u get cor temps that correlate.....

3,000,000/660nnm=4545K
&
3,000,000/440nnm=6818k

Making the bulbs of choice 6500k and 4100k as opposed to 2700k

Thats just ghe numbers.. I know what re recite as far as veg 65 bloom 27
 

churchhaze

Well-Known Member
Im about fo grow with 6500 &4100k in tandem because if you use weins law and divide the max absorbtion of nnm in chlorophyll A&B of 660&440 u get cor temps that correlate.....

3,000,000/660nnm=4545K
&
3,000,000/440nnm=6818k

Making the bulbs of choice 6500k and 4100k as opposed to 2700k

Thats just ghe numbers.. I know what re recite as far as veg 65 bloom 27
You were wrong about what Wein's law is on another thread, so instead of educating yourself, you come here and say the same stuff again?

Wein's law is for black body sources! Color temperature for other sources doesn't follow those rules and tell you very little about the spectral power distribution. Color temperature is related to how a human perceives the light. Many spectral power distributions have the same color temperature, so using something like Wein's law the way you are is just plain wrong.

This is what spectral power distribution looks like for black body sources.





Notice how 4000k black body, 4000k MH, and 4000k fluorescent have completely different spectral distributions.

Even the 2700K florescent still are very low in red. It's that 590nm peak that generally gets bigger and the blue and green peaks peak smaller. The peaks themselves don't shift over in wavelength to become more blue or red.
 
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FATBOYFRESH

Well-Known Member
You were wrong about what Wein's law is on another thread, so instead of educating yourself, you come here and say the same stuff again?

Wein's law is for black body sources! Color temperature for other sources doesn't follow those rules and tell you very little about the spectral power distribution. Color temperature is related to how a human perceives the light. Many spectral power distributions have the same color temperature, so using something like Wein's law the way you are is just plain wrong.

This is what spectral power distribution looks like for black body sources.





Notice how 4000k black body, 4000k MH, and 4000k fluorescent have completely different spectral distributions.

Even the 2700K florescent still are very low in red. It's that 590nm peak that generally gets bigger and the blue and green peaks peak smaller. The peaks themselves don't shift over in wavelength to become more blue or red.
So what is weins law? Or its importance?
 

FATBOYFRESH

Well-Known Member
This guy follows my post with adverserial spirit.. But doesnt respond to my question.... I know it doesnt take this long to answer..... I know it took longer for you to find this post..comment on iy... Add charts etc.... Lol.... What do you use
 
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