True power of lighting.

Roullette

Well-Known Member
This topic I am doing is on how Light effects your plant and what lighting and spectrum does.

Lets start off with the basics. As many of you know lighting is a pretty important part in your plants building blocks of life.

Every plant has Chlorophyll, And most plants have Chlorophyll a. and Chlorophyll b.Chlorophyll makes it possible for plants to convert dioxide and water, in the presence of sunlight, into oxygen and glucose. This is a Process of Photosyntheses.Chlorophyll is a energy in the form of sugary carbohydrates, which is the builder of your plants growth and also gives it the nice green look we all love.

Since the Chlorophyll is green thats the light spectrum that is reflected the plant leaves are green and the green spectrum isn't the only reflected spectrum of light.Far-red light is also reflected. Far-red is just outside the visible light spectrum. We can not see that spectrum of light but can be sensed by the plants. when there are other plants close by because of the increase of far-red wavelengths the other plants reflect. This tells the plant that there is other plants next to it and the plant will make the plant compete with other plants to grow faster in a race for light But keep in mind the plants do not absorb the far-red spectrum to grow.

Since the plant has 2 types of chlorophyll photoreceptors. The different side groups in the 2 chlorophylls seprate the absorption spectrum to slightly different wavelengths, so that light that is not significantly absorbed by chlorophyll a. But will instead be captured by chlorophyll b, which absorbs strongly at that wavelength.These two kinds of chlorophyll work with each other in absorbing sunlight.

Plants can obtain all their energy requirements from the blue and red parts of the spectrum, In early stages a young plant uses mostly the blue spectrum which is why a lot of people use MH bulbs and 6500 Kelvin CFLs. The Blue spectrum promotes the Growth of the plant itself, this spectrum of light simulated the light put off by the sun in the spring time. And in later stages of the plant uses mostly the red spectrum which is why people use HPS bulbs and 2700 Kelvin HO Fluorescents. The Red spectrum promoted the growth of the flowers of the plant, this spectrum of light simulates the light put off by the sun in the late fall.

Basically the blue spectrum gets your plant get ready to be an adult and the red spectrum gets your plant ready to produces flowers/seeds to make more plants.

From what I have researched 6500K spectrum CFLs are the "ideal" blue spectrum bulbs. You do have to get more CFLs over and around your plant then MH bulbs because of the Lumen out put of CFLs. Same with the amount of HO Fluorescents compared to the HPS due to lower Lumens per bulb.

Now a Lumen is a unit of measurement of light. It measures light much the same way. Now 1 foot-candle is how bright the light is one foot away from the source. A lumen is a way of measuring how much light gets to what you want to light. A Lumen is equal to one foot-candle falling on one square foot of area.

1-400 watt HPS bulb = 10-54 watt HO Fluors which equals 50,000 lumens.

Since a lumen is a measurement of light there for 10. 54 watt HO Fluors will light the same area as a 400 watt HPS.But the HPS has a much higher PAR rating then HO Fluorescent.

PAR rating is Photosynthetically Active Radiation.

PAR designates the spectral range of solar light from 400 to 700 nanometers that is useful to plants in the process of photosynthesis.The spectral corresponds with the range of light visible to the human eye.

Basically PAR is how strong the rays of the sun are and every bulb has a different PAR rating.Winter, suns further way giving a smaller PAR rating. Summer, suns closer higher PAR rating.

HPS have a high PAR rating (about 130-140 PAR watts) and MH has a high PAR rating aswell (around 130-140 PAR watts). Which if to close can burn the plant. Since the HO Fluorescents have a low PAR rating it allows you to get the bulbs real close to the colas of the plants without damaging the plant(about 50-80 PAR watts).no manufacturer will give a PAR rating of there bulbs, why i do not know.

In my personal opinion on researching on all of this I think HPS is a better source of lighting due to the high red spectrum allowing the buds to get the full effect of fall simulated lighting allowing bigger buds.
But I also think that you can get just as good quality buds from HO Fluorescents. You just sacrifice quantity not quality.

I recommend using 6500K CFLs for vegging. you can use mix spectrum HPS bulbs without sacrificing much results with comparison to the CFLS and MHs.

I also posted pictures to help better understand what to look for in lighting.

I hope this will help a lot of growers decide on what type of lighting to go with.
 

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nastynate101

Well-Known Member
nicely written, you get a kudos = to an A+ on your report, I would do it either in a CFL or T5 flouro in the blue spectrum both around 6500K and then HPS for flowering is ideal, just depends on space and privacy really. I have not bought any CFL's just fluors so far, I have seen 75% of people on here spend as much on CFL's and materials to use those CFL's as it would take to get a 400 watter delivered, but like I said its all about your privacy, if you live alone you can do big light :)
 

power2me

Active Member
Nice job. I was looking some info on Color temp and veging. So I got 400 watt MH/HPS 4000k, from the charts u posted sounds like I needa get a 5000 or 5500 for better veg. Does this sound about right?
 

Roullette

Well-Known Member
yea you wanna get the bluest spectrum for veggin it simulates the sun during spring time and the plant will use that lighting for making sugars to get her self ready for flowering. then switch to the red spectrum for flowering since u have an hps your set..
 

rbahadosingh

Well-Known Member
would a mh conversion bulb be ok also? i have a growbright mh conversion bulb. says the color temperature is 6000k.
 

Roullette

Well-Known Member
hells ya. from what ive been reading on worms way theres a bulb out or coming out thats a HPS/ MH combo buld.. needing the duel electric ballast to run. id look into that. imma try that bulb next.
 

Earl

Well-Known Member
I see you have been doing your home work.

Very nicely written post.

Here are the charts you posted,
and a couple more.






I have been using a MH conversion bulb,
but they are not very efficient.
My conversion bulb is 38,000 lm
and the MH bulb is 55,000 lm

I recommend getting a digital ballast,
that way you can run
the MH or HPS
with the same fixture,
and you get to use the 55k lm mh bulbs.

I use SunMaster and Eye Hortilux bulbs

I like to have both during veg,
then go HPS only for almost all of flower
then finish with MH and CFLs,
during my extreme "RO only" flush.
 

Roullette

Well-Known Member
This explains how lumens are measured... Will help figure out how much a HPS 400,600,1000 watt can light in an area. Also has reflector values.

Lumens, Footcandles, Candlepower, Measuring Light Output

This is a paste from that site.

A LUMEN is a unit of measurement of light. It measures light much the same way. Remember, a foot-candle is how bright the light is one foot away from the source. A lumen is a way of measuring how much light gets to what you want to light! A LUMEN is equal to one foot-candle falling on one square foot of area.
So, if we take your candle and ruler, lets place a book at the opposite end from the candle. We'd have a bit of a light up if we put the book right next to the candle, you know. If that book happens to be one foot by one foot, it's one square foot. Ok, got the math done there. Now, all the light falling on that book, one foot away from your candle equals both…….1 foot candle AND one LUMEN!


And I found this on another sight.




This is a real easy way to find the number of Lumens Per Square Foot (Foot-Candles) you are getting from your bulb at any distance. It’s the same value you’d get using the more complicated formulas below, but is real quick and simple.

* Multiply the lumen output of the bulb by 45.84.
* Divide by the number of inches from the bulb squared.

It’s that simple.

This would be based on the use of a typical 120° reflector. If the reflector cast a different angle, then we would need to manipulate the formula a bit as is shown below. It’s all based on spherical geometry.


This is the longer detailed formulas for calculating the number of Foot-Candles (Lumens/ft.²) coming from a bulb:

The divisor must be equal to the actual area that is being illuminated by the bulb, which is not based on your floor plans. The divisor in Formula A is calculating a spherical propagation of light, which is what the light is really illuminating.

Formula A:
Foot-Candles = Lumens ÷ (4 × Pi × d²)

Where:
d = The distance from the bulb in feet.
Pi = 3.14159

If you wanted to know how many Foot-Candles of light are striking your plant 10" away from a 400 watt HPS that puts out 50,000 lumens you would do this:

Foot-Candles = 50000 ÷ (4 × Pi × (10/12)²)
Foot-Candles = 50000 ÷ (12.57 × 0.6944)
Foot-Candles = 50000 ÷ ( 8.729)
Foot-Candles = 5,728

So, there are 5,728 Foot-Candles of light hitting your plant 10" from a 400 watt HPS with no reflector.

Now, because we are using reflectors it will actually be more. Let's calculate how many Foot-Candles hit your plant 10" away with a typical 120° reflector.

Formula B:
Foot-Candles = Lumens ÷ (2 × Pi × d² × (1 - cos(A/2)))

Where:
A = The degree of the reflector. (Most of us have 120° reflectors)
d = The distance from the bulb in feet.
Pi = 3.14159

To make this easier we already know the value of d² when the distance is 10" from the bulb. That value as calculated above is 0.6944.

Foot-Candles = 50000 ÷ ( 2 Pi × d² (1 - cos(120/2)))
Foot-Candles = 50000 ÷ ( 2 Pi × d² (1 - cos(60)))
Foot-Candles = 50000 ÷ ( 2 Pi × d² (1 - 0.5))
Foot-Candles = 50000 ÷ ( 6.283 × 0.6944 × 0.5)
Foot-Candles = 50000 ÷ (2.181)
Foot-Candles = 22,918

Im taking no credit for this math... just putting up for more lighting material.
 

skunk8522

Active Member
very nice but there is also one thing i have read that it is better to have two 600 watt bulbs rather then just one 1000 watt bulb 4 an even light distribution in the room so that the plants in the corner are getting just as much light as possible "marijuana horticulture indoor/outdoor growers bible"
 

Earl

Well-Known Member
If you are planning on 1000w lights ,
you also need to include a light mover,
to prevent burning,
and to cover the area evenly.

Coverage is why two 6oos are better,
and thee 400s would be best.

Three 400s on light movers would be awesome.

Have you seen the spinners?
Life Light Tech Sun Spinner 900W 120V

Supposed to work really great, for about 2K+$
 

Rsixxer

Well-Known Member
I would be curious to the benefits of using the new 430 watt Son Agro bulbs. I know there is an added blue spectrum, but is it enough to use over CFL's in vegging? Anybody?
 
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