yeah B U B B A
Well-Known Member
i see some people using the purple l.e.d lights. whats the pros and cons using that kind of light.? im using t5 flurescent 65k 10k lumens.!
grow lights
- Thread starter yeah B U B B A
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Doer
Well-Known Member
To me it is all about foot candle, not lumen. Lumen are the visible light we see, sort of the middle of the sun power 5000K. That is not the good stuff for plants. They need the ends, not the middle of the spectrum.
Foot candles measure intensity of the photon stream. Our eyeball is capable of seeing a candle at 10 miles, in favorable conditions. Sunlight max, for an hour a day for one month of the year, is 10,000 foot candles.
When I place my 1000w HPS at 26 inches, that is Sun Power or 10,000 foot candles, centering around 2700K, which plants love, but looks like sodium vapor to us.
So, this gives you an idea of watts/distance/intensity/color. For Veg we use T5 or I use 250w CFL at a higher temperature/Frequency/Color @ 6500K....Blue..
It give Sun Power at about 6-8 inches.
So, don't be a gearhead, like I was, be a grower. And growers are all about efficiency and effectiveness,
So, tell me if you can find LEDs at 1000w that list foot candles. I can't. And I have never seen a grow get to excellence under LED... I could be wrong.
But, the same formula applies. Even in the PAR ranges, which we can see by, quite clearly, I don't see the foot candles yet, from LED.
And you can get supposed, 1000w LED, but for $600 on Ebay. But, they will not list the foot candles.
The only thing that counts is your results. T5 is all you need for veg. And if you can get some 2700 CFL, those work fine for bloom. Total watts is all that matters. (not eye apparent, illumination,i.e. lumens) Watts is yield. So, the Grail is a gram per real watt.
I think I will top 0.5 per watt this time.
Foot candles measure intensity of the photon stream. Our eyeball is capable of seeing a candle at 10 miles, in favorable conditions. Sunlight max, for an hour a day for one month of the year, is 10,000 foot candles.
When I place my 1000w HPS at 26 inches, that is Sun Power or 10,000 foot candles, centering around 2700K, which plants love, but looks like sodium vapor to us.
So, this gives you an idea of watts/distance/intensity/color. For Veg we use T5 or I use 250w CFL at a higher temperature/Frequency/Color @ 6500K....Blue..
It give Sun Power at about 6-8 inches.
So, don't be a gearhead, like I was, be a grower. And growers are all about efficiency and effectiveness,
So, tell me if you can find LEDs at 1000w that list foot candles. I can't. And I have never seen a grow get to excellence under LED... I could be wrong.
But, the same formula applies. Even in the PAR ranges, which we can see by, quite clearly, I don't see the foot candles yet, from LED.
And you can get supposed, 1000w LED, but for $600 on Ebay. But, they will not list the foot candles.
The only thing that counts is your results. T5 is all you need for veg. And if you can get some 2700 CFL, those work fine for bloom. Total watts is all that matters. (not eye apparent, illumination,i.e. lumens) Watts is yield. So, the Grail is a gram per real watt.
I think I will top 0.5 per watt this time.
sativa indica pits
Active Member
that is a good run down!! led's are way to pricey for me.
Doer
Well-Known Member
Here is the scam.
They are not very bright lights. And those color lens just reduce the photon intensity. You can say what you want, but foot candles tell the story. These LED guys want us to think the good stuff, illumination is not visible to the naked eye. BS.
Can you look at the sun? No. How about a 1000w of HPS or MH from 26"? HA. I pity the fool.
(done that)
These LEDs, are not bright enough. They don't have the foot candles.
They are not very bright lights. And those color lens just reduce the photon intensity. You can say what you want, but foot candles tell the story. These LED guys want us to think the good stuff, illumination is not visible to the naked eye. BS.
Can you look at the sun? No. How about a 1000w of HPS or MH from 26"? HA. I pity the fool.
(done that)These LEDs, are not bright enough. They don't have the foot candles.
mattycakes
New Member
this might be a dumb ? butt... can u run a 400 watt mh bulb off a 400 what ballast?
yeah B U B B A
Well-Known Member
so if i continue using flurescent lights., i need to drop from 65k lights to 27k lights.!? but i didnt get the answer about the color "purple" and not "white"
Doer
Well-Known Member
When you talk about Kelvins, you are talking about the temperature above absolute Zero. Those temps map to frequency, and the frequency in Nano-meters, maps directly to colors and those map directly back into Kelvin. So, Kelvin is temp. in this universe. Those Temps are visible to us as colors.
When I hang my CFL with the HPS, like I am doing now, it is very obvious. The CFL is bluish at 6500K and the HPS looks orange at 2700K.
So, the spectrum of color is all about temperature. And that is how we know what elements are in a far off star, for example, just by analysis of the light.
When I hang my CFL with the HPS, like I am doing now, it is very obvious. The CFL is bluish at 6500K and the HPS looks orange at 2700K.
So, the spectrum of color is all about temperature. And that is how we know what elements are in a far off star, for example, just by analysis of the light.
yeah B U B B A
Well-Known Member
so the purple have better temp than the bluish or the orange color.? i know the wave spectrum but not the temp..
Doer
Well-Known Member
What I am trying to tell you it is the same thing.
Degrees Kelvin above Absolute Zero, (some 400 degrees in Kelvins below Zero Centigrade) map directly into the wave spectrum, in nano-meters.So, instead of the mid-deep orange red, we say, 2700K or ~670 nm frequency. We only call them colors.
As to what is better, well, check the sunlight. We could generate sun power,in all frequencies but we do not need to. We found that if you switch colors between veg and bloom that is all the color or frequency we need. So we can pump watts into that and not waste money on the rest.
yeah B U B B A
Well-Known Member
oh kay i got you now
Greengenes707
Well-Known Member
Here is the scam.
They are not very bright lights. And those color lens just reduce the photon intensity. You can say what you want, but foot candles tell the story. These LED guys want us to think the good stuff, illumination is not visible to the naked eye. BS.
Can you look at the sun? No. How about a 1000w of HPS or MH from 26"? HA. I pity the fool.
These LEDs, are not bright enough. They don't have the foot candles.
Your thinking is close but foot candles is still the wrong unit.
PAR measure in µmols(micro moles) tell the actual amount of photons falling in an area. It is what all scientist use in horticulture...not foot candles, lumens, or anything else. µmols easily convert/add up to moles of light per day which is then DLI(dally light intake) and corresponds to yields. Light and yield are directly related and µmols are what tell you how much light is actually there in an even and un bias measurement.
SnapsProvolone
Well-Known Member
Well put. I agred wholeheartedly.
Doer
Well-Known Member
No, I think PAR is covered. We need PAR watts. We require PAR footcandles or µmols of photon energy, Footcandle means the flux density of the photon steam. That is why distance is the handmaiden of footcandles. Micro-moles of what? Photons. So, take a square meter, 25 inches away from 1000w HPS. 10,000 footcandles of photon density in the square meter.
Most horticultural researchers measure instantaneous light in micromoles (μmol) per square meter (m -2) per second (-1), or: μmol·m 2·s-1of PAR. This quantum unit quantifies the number of photons (individual particles of energy) used in photosynthesis that fall on a square meter (10.8 square feet) every second. However, this light measurement also is an instantaneous reading.
http://www.extension.purdue.edu/extmedia/HO/HO-238-W.pdf
And if we use calculus, we can derive an integration over time. The Integral PAR. It is how much PAR changes day to day, and month to month in sunlight.
http://en.wikipedia.org/wiki/Foot-candle
Since light intensity is the primary factor in the photosynthesis of plants, horticulturalists often measure and discuss optimum intensity for various plants in foot-candles. Full, unobstructed sunlight has an intensity of approximately 10,000 fc. An overcast day will produce an intensity of around 1,000 fc. The intensity of light near a window can range from 100 to 5,000 fc, depending on the orientation of the window, time of year and latitude.
----------
So, it is all more or less exactly the same thing. But, lumen are projected form a source and footcandles are recieved by the leaf. And PPF is the sum over time.
[TABLE="align: center"]
[TR]
[TD="colspan: 2"][h=3]PPF (μmol m[SUP]-2[/SUP] s[SUP]-1[/SUP]) to Foot-candles[/h] [/TD]
[TD="colspan: 2"] [h=3]Foot-candles to PPF (μmol m[SUP]-2[/SUP] s[SUP]-1[/SUP])[/h] [/TD]
[/TR]
[TR]
[TD]Sunlight[/TD]
[TD="width: 85"]5.01[/TD]
[TD]Sunlight[/TD]
[TD="width: 85"]0.200[/TD]
[/TR]
[TR]
[TD]Cool White Fluorescent Lamps
[/TD]
[TD]6.87[/TD]
[TD]Cool White Fluorescent Lamps
[/TD]
[TD]0.146[/TD]
[/TR]
[TR]
[TD]High Pressure Sodium Lamps[/TD]
[TD]7.62[/TD]
[TD]High Pressure Sodium Lamps[/TD]
[TD]0.131[/TD]
[/TR]
[TR]
[TD]High Pressure Metal Halide Lamps[/TD]
[TD]6.60[/TD]
[TD]High Pressure Metal Halide Lamps[/TD]
[TD]0.152[/TD]
[/TR]
[/TABLE]
So, Sun Power on the leaf is distance from source and time of exposure. So, we are correct to say, the only thing that matter is the energy that made it to the leaf.
These plants can move from well under sun power, for seedlings to well over for Bloom. The Bloom FC at 3000 meters altitude for the landrace strains is 16,000 FC.
Greengenes707
Well-Known Member
Sorry bro your wrong no matter how much you like foot-candles. They are 1 LUMEN/meter^2...are a bias measurement. Based on your thinking the whole world of professional horticulture uses the wrong measurements.
Par light measured in µmols/m^2/s(PPFD...the instantaneous reading). But you can look at a light in PPF...and is the total lPAR photons emitted by the source.
PPFD(intintaneous) is also the intensity. The sun emits 2000µmols in the peak summer. A 1000w hortilux will hit about 1000µmols at 24" from the canopy. The new double ended phillips bulbs will do 1400µmols @24" and a hortilux in a n OG hood can hit 1800µmols.
You can convert it to foot-candles all you want...but the measurement of µmols of photons with in the PAR range is all that matters. You can look at radiant W sometimes but it takes more converting to use that as an actual horticulture tool. It has been shown that 7-10µmols is used in each photosynthesis conversion...and it was shown that way because PAR µmols is the correct and scientific way to express light for plants.
Par light measured in µmols/m^2/s(PPFD...the instantaneous reading). But you can look at a light in PPF...and is the total lPAR photons emitted by the source.
PPFD(intintaneous) is also the intensity. The sun emits 2000µmols in the peak summer. A 1000w hortilux will hit about 1000µmols at 24" from the canopy. The new double ended phillips bulbs will do 1400µmols @24" and a hortilux in a n OG hood can hit 1800µmols.
You can convert it to foot-candles all you want...but the measurement of µmols of photons with in the PAR range is all that matters. You can look at radiant W sometimes but it takes more converting to use that as an actual horticulture tool. It has been shown that 7-10µmols is used in each photosynthesis conversion...and it was shown that way because PAR µmols is the correct and scientific way to express light for plants.
Doer
Well-Known Member
I think you want to argue over nothing and begin to get tiresome. I don't care. I have been studying this stuff, in depth for 20 years.
And I am not even discussing this. It is all the same thing, it all maths out. And I just showed references while you steam for a debate about it with nothing but a sonorous tone of lecture.
It is not debatable. FC over time and micro-moles over time, is the same thing.
And you are so off base, You cannot buy lighting based on Micro-moles, but you can buy according to foot-candles which will math the same thing,
mm AND fc are taking about exactly the same thing. PAR is just the fequencies. We want watts in those frequencies and how far we put the light is the
footcandles and Micro-moles...just math.
PAR µmols is the correct and scientific way to express light for plants.
Suddenly we trying to be correct and sicentific ina growers from. HA. Both are correct and both are scientific,. Both FC and MM, refer to photon density. And both will give me photon spread.
But, show me any commercial grower that worries about this. No. They buy the fancy quantum PAR meters, and then can get PAR readings from under the strawberry leaves.
We are not conducting science. We are buying lights. There is no debate here.
And I am not even discussing this. It is all the same thing, it all maths out. And I just showed references while you steam for a debate about it with nothing but a sonorous tone of lecture.
It is not debatable. FC over time and micro-moles over time, is the same thing.
And you are so off base, You cannot buy lighting based on Micro-moles, but you can buy according to foot-candles which will math the same thing,
mm AND fc are taking about exactly the same thing. PAR is just the fequencies. We want watts in those frequencies and how far we put the light is the
footcandles and Micro-moles...just math.
PAR µmols is the correct and scientific way to express light for plants.
Suddenly we trying to be correct and sicentific ina growers from. HA. Both are correct and both are scientific,. Both FC and MM, refer to photon density. And both will give me photon spread.
But, show me any commercial grower that worries about this. No. They buy the fancy quantum PAR meters, and then can get PAR readings from under the strawberry leaves.
We are not conducting science. We are buying lights. There is no debate here.
Greengenes707
Well-Known Member
It's been 2 post man and the first was that you were close to right but with the wrong unit of measurement(which no matter how you spin it I was right). If you know all about it then it you should have used the correct units from the start.
Your right this is about buying lights...a puple led where lumens and foot-candle mean near to nothing. foot-candles and lumens will be low as where PAR may not be. That is because you are using a bias/skewed/wrong unit of measurement. A foot candle is 1lumen per square meter. Growing is a science and our favorite plant isn't an accept ion. And just because we are not all into techy stuff doesn't mean that when it is presented it is wrong because your way is sorta close.
Then only reason I argue is because the original posted asked about the lights and referenced lumens...then you came in and said foot candles is all that matters. Which is wrong, but if you were to use PAR µmols in the place of foot-candle your explanation would have been sound.
To take this further it has to do with the LER(luminaire efficiency rating) that led's have and if using white led's creates a whole new problem to calculate the spectral curve's LER. LER is the amount of lumens a soucre would put out if it was 100% efficient. Using LER is the only way that a lumen or foot-candle or lux reading is useful.
And true horticulture bulbs like hortilux and phillips do show PPF. That doesn't mean all that will get to the canopy but it is a quanta reading not a brightness reading which is what matters.
From purdue
Just as important, foot-candles are photometric units based on the amount of visible light de-tected by the human eye (primarily green light). That means foot-candles are focused on peopleand not appropriate for indicating plant photosynthesis.
Most horticultural researchers measure instantaneous light in micromoles (μmol) per squaremeter (m-2) per second (s-1), or: μmol·m-2·s-1 of PAR. This quantum unit quantifies the number ofphotons (individual particles of energy) used in photosynthesis that fall on a square meter (10.8square feet) every second.
EDIT
I am done talking about it. I have shared what matters and anyone reading it can go look it up in a real botany/biology book what a plant actually uses and what is important.
Your right this is about buying lights...a puple led where lumens and foot-candle mean near to nothing. foot-candles and lumens will be low as where PAR may not be. That is because you are using a bias/skewed/wrong unit of measurement. A foot candle is 1lumen per square meter. Growing is a science and our favorite plant isn't an accept ion. And just because we are not all into techy stuff doesn't mean that when it is presented it is wrong because your way is sorta close.
Then only reason I argue is because the original posted asked about the lights and referenced lumens...then you came in and said foot candles is all that matters. Which is wrong, but if you were to use PAR µmols in the place of foot-candle your explanation would have been sound.
To take this further it has to do with the LER(luminaire efficiency rating) that led's have and if using white led's creates a whole new problem to calculate the spectral curve's LER. LER is the amount of lumens a soucre would put out if it was 100% efficient. Using LER is the only way that a lumen or foot-candle or lux reading is useful.
And true horticulture bulbs like hortilux and phillips do show PPF. That doesn't mean all that will get to the canopy but it is a quanta reading not a brightness reading which is what matters.
From purdue
Just as important, foot-candles are photometric units based on the amount of visible light de-tected by the human eye (primarily green light). That means foot-candles are focused on peopleand not appropriate for indicating plant photosynthesis.
Most horticultural researchers measure instantaneous light in micromoles (μmol) per squaremeter (m-2) per second (s-1), or: μmol·m-2·s-1 of PAR. This quantum unit quantifies the number ofphotons (individual particles of energy) used in photosynthesis that fall on a square meter (10.8square feet) every second.
EDIT
I am done talking about it. I have shared what matters and anyone reading it can go look it up in a real botany/biology book what a plant actually uses and what is important.
yeah B U B B A
Well-Known Member
man yall taking me back to biology class lol.. check it., keep it coming cause i do wanna know but lol can yall break this down in smaller terms for ME.?
Greengenes707
Well-Known Member
Do you have a link to the led light your thinking about?
Is your current setup a 24" 4 bulb T5 setup?
What size is your grow space?
Is your current setup a 24" 4 bulb T5 setup?
What size is your grow space?
yeah B U B B A
Well-Known Member
no i do not have a link but its on ebay and its a 10 band led and its 110w.!
im currently using 24" T5 dual band bulbs 65k with a 10k lumens.!
my tent is 4ft x 4ft x 10ft.!
