skiweeds
Active Member
i didnt write this, i found it on high times and thought i would share. there is more to it but i pretty much just copied the info on spectra. its more about LEDs but explains the importance of spectra and different pigments.
currently i only use a mh for veg and hps for flowering(amazing results with just that). after reading this though, i am considering adding some supplement lighting so my plants are getting more of the spectrum(s) the mh and hps dont deliver enough of. hope you guys find this as interesting as i.
[FONT=Verdana, Arial, Helvetica, sans-serif][FONT=Verdana, Arial, Helvetica, sans-serif]All plants absorb light via pigments such as chlorophyll A, chlorophyll B and carotenoids. This light energy, also known as photons, is converted into usable plant energy by the excitation of electrons within the plant cells. This energy becomes the major catalyst in photosynthesis.
[/FONT][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]Without this energy, the plant would be unable to produce food for itself and grow. Without this energy, there would be no buds or resin production of any kind.
A graphic of the absorption process within leaves is depicted in Figure 1.1. The graph shows the absorption rates of two separate pigments (chlorophyll A and B) and breaks down the absorption spectrum by wavelength or color. With this knowledge, it is much easier to see the importance of providing proper spectrum for indoor marijuana gardens. As a guide to better understanding what bulbs can and cannot supply, we have compiled a few graphs to illustrate some of the more prominent bulb types on the market today (see figures 1.2, 1.3 and 1.4).
One important characteristic that isn't displayed on these charts, however, is the power of the light emitted. Ironically, the bulbs with the best light spectrum are actually the weakest in terms of strength. In fact, a regular incandescent household light bulb actually has a superior spectrum compared to HPS or MH bulbs, but the power just isn't there. When bulbs lack the strength for their light to penetrate or even reach garden canopies, their value becomes limited.
[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]Bulbs must be able to deliver their light to cannabis gardens with a force as close to the sun's natural power as possible. Unfortunately, bulbs like fluorescents or incandescents are only strong enough for supplemental lighting, or for use in nursery lamps when baby clones are still rooting. Using lights that aren't powerful enough for adults will result in spindly, leafy plants as their branches stretch to gather more light.
Another important consideration regarding spectrum involves using supplemental lighting to compensate for the lack of a full spectrum. A well-known experiment conducted in 1950 by Robert Emerson led to the discovery of what we now call the Emerson Enhancement Effect. In principal, the effect states that when shorter wavelengths (i.e., blues or oranges) are supplied along with the longer wavelengths (such as reds at 690 nm and higher), absorption and photosynthesis occur at a faster rate than the sum of both colors acting alone. The reason this happens is because separate photosynthetic processes, called photosystems, occur within the leaves and are related to the specific leaf pigments discussed above.
As research progressed, it turned out that these systems can work together within leaves and that each actually works better when functioning together. Thus, it may be best for indoor growers to mix opposing wavelengths when supplementing gardens rather than use the standard HPS/ MH mix. Looking at the spectral coverage of various bulbs, we notice that fluorescent bulbs are an excellent option for supplemental light. Many people first thought that LED's would also be a great [/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]source of supplemental light, but as developments continue, some are now claiming that they may be the next all-in-one lamp.
With prices dropping in LED technology, more manufacturers like HID Hut will be able to produce fuller-spectrum LED lights, making the future even brighter than we might have anticipated.
The graph shows the absorption rates of two separate pigments (chlorophyll A and B) and breaks down the absorption spectrum by wavelength or color. With this knowledge, it is much easier to see the importance of providing proper spectrum for indoor marijuana gardens. As a guide to better understanding what bulbs can and cannot supply, we have compiled a few graphs to illustrate some of the more prominent bulb types on the market today.
One important characteristic that isn't displayed on these charts, however, is the power of the light emitted. Ironically, the bulbs with the best light spectrum are actually the weakest in terms of strength. In fact, a regular incandescent household light bulb actually has a superior spectrum compared to HPS or MH bulbs, but the power just isn't there. When bulbs lack the strength for their light to penetrate or even reach garden canopies, their value becomes limited.
http://hightimes.com/microsites/led/images/led_1_1.jpg
http://hightimes.com/microsites/led/images/led_2_1.jpg
http://hightimes.com/microsites/led/images/led_3_1.jpg
http://hightimes.com/microsites/led/images/led_4_1.jpg
also, take a look at this experiment.
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]In three separate trials, a high-powered LED (prototypes of HID Hut's UFO) was run in side-by-side experiments-once against a 400-watt MH bulb, once against a 400-watt HPS bulb, and once against a 600-watt HPS bulb. These trials used exactly the same conditions on both sides of the fence. The plants were cuttings taken from a single mother; the medium and grow systems were the same; and the nutrients and atmospheric conditions were kept identical. The only variable was the lamp provided. And, as usual, the results varied.
In Trial A, the clones were placed in a three-by-six-foot box that was divided evenly in half. An ebb-and-flow table on each side shared the same grow medium and reservoir. In the end, the LED lamp yielded 12% more than its counterpart, the 400-watt MH.
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]In Trial B, similar systems again pitted the UFO against a 400-watt HPS, only this time the LED side took an extra week to finish. Some concern arose over stretching, as the clone grew to touch the UFO. This resulted in a decision to increase the blue diodes in a second prototype, and it may lead to an increase in wavelength for the red diodes, according to the manufacturer. In the end, the LED side yielded 5% less than the HPS side did.
However, it was reported in Trial B that there were markedly different potencies, with the LED plant producing much more resin. Speculation exists that the shortage of wavelengths aided in this process, as abnormal stresses have been known to increase the production of resin glands.
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]Final calculations taking into consideration the extra week of flowering time on the LED side found that in terms of grams yielded per kilowatt hour (KwH) consumed, the HPS yield was one-fourth that of the LED side.
In Trial C, the grower found similarities to both previous trials. While the LED yielded less than its counterpart, this test pushed the limits of the LED by pitting it against a stronger 600-watt HPS bulb. Resin production on this Cali-O strain was up after just four weeks of flowering, but in the end, the yield was around 20% less. However, the grower did note that the amount of money saved in electric costs compared against the costs of the 600-watt HPS was almost enough to offset the profits lost on yield. An interesting side note in this trial was that the plant on the LED side needed considerably less watering than the plant on the HPS side. It is possible that this is due to lower surface temperatures in the soil medium, or because the plant wasn't driven as hard and thus drank less. [/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]
source- http://hightimes.com/microsites/led/information.inc.php
[/FONT]
currently i only use a mh for veg and hps for flowering(amazing results with just that). after reading this though, i am considering adding some supplement lighting so my plants are getting more of the spectrum(s) the mh and hps dont deliver enough of. hope you guys find this as interesting as i.
[FONT=Verdana, Arial, Helvetica, sans-serif][FONT=Verdana, Arial, Helvetica, sans-serif]All plants absorb light via pigments such as chlorophyll A, chlorophyll B and carotenoids. This light energy, also known as photons, is converted into usable plant energy by the excitation of electrons within the plant cells. This energy becomes the major catalyst in photosynthesis.
[/FONT][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]Without this energy, the plant would be unable to produce food for itself and grow. Without this energy, there would be no buds or resin production of any kind.
A graphic of the absorption process within leaves is depicted in Figure 1.1. The graph shows the absorption rates of two separate pigments (chlorophyll A and B) and breaks down the absorption spectrum by wavelength or color. With this knowledge, it is much easier to see the importance of providing proper spectrum for indoor marijuana gardens. As a guide to better understanding what bulbs can and cannot supply, we have compiled a few graphs to illustrate some of the more prominent bulb types on the market today (see figures 1.2, 1.3 and 1.4).
One important characteristic that isn't displayed on these charts, however, is the power of the light emitted. Ironically, the bulbs with the best light spectrum are actually the weakest in terms of strength. In fact, a regular incandescent household light bulb actually has a superior spectrum compared to HPS or MH bulbs, but the power just isn't there. When bulbs lack the strength for their light to penetrate or even reach garden canopies, their value becomes limited.
[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]Bulbs must be able to deliver their light to cannabis gardens with a force as close to the sun's natural power as possible. Unfortunately, bulbs like fluorescents or incandescents are only strong enough for supplemental lighting, or for use in nursery lamps when baby clones are still rooting. Using lights that aren't powerful enough for adults will result in spindly, leafy plants as their branches stretch to gather more light.
Another important consideration regarding spectrum involves using supplemental lighting to compensate for the lack of a full spectrum. A well-known experiment conducted in 1950 by Robert Emerson led to the discovery of what we now call the Emerson Enhancement Effect. In principal, the effect states that when shorter wavelengths (i.e., blues or oranges) are supplied along with the longer wavelengths (such as reds at 690 nm and higher), absorption and photosynthesis occur at a faster rate than the sum of both colors acting alone. The reason this happens is because separate photosynthetic processes, called photosystems, occur within the leaves and are related to the specific leaf pigments discussed above.
As research progressed, it turned out that these systems can work together within leaves and that each actually works better when functioning together. Thus, it may be best for indoor growers to mix opposing wavelengths when supplementing gardens rather than use the standard HPS/ MH mix. Looking at the spectral coverage of various bulbs, we notice that fluorescent bulbs are an excellent option for supplemental light. Many people first thought that LED's would also be a great [/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]source of supplemental light, but as developments continue, some are now claiming that they may be the next all-in-one lamp.
With prices dropping in LED technology, more manufacturers like HID Hut will be able to produce fuller-spectrum LED lights, making the future even brighter than we might have anticipated.
The graph shows the absorption rates of two separate pigments (chlorophyll A and B) and breaks down the absorption spectrum by wavelength or color. With this knowledge, it is much easier to see the importance of providing proper spectrum for indoor marijuana gardens. As a guide to better understanding what bulbs can and cannot supply, we have compiled a few graphs to illustrate some of the more prominent bulb types on the market today.
One important characteristic that isn't displayed on these charts, however, is the power of the light emitted. Ironically, the bulbs with the best light spectrum are actually the weakest in terms of strength. In fact, a regular incandescent household light bulb actually has a superior spectrum compared to HPS or MH bulbs, but the power just isn't there. When bulbs lack the strength for their light to penetrate or even reach garden canopies, their value becomes limited.
http://hightimes.com/microsites/led/images/led_1_1.jpg
http://hightimes.com/microsites/led/images/led_2_1.jpg
http://hightimes.com/microsites/led/images/led_3_1.jpg
http://hightimes.com/microsites/led/images/led_4_1.jpg
also, take a look at this experiment.
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]In three separate trials, a high-powered LED (prototypes of HID Hut's UFO) was run in side-by-side experiments-once against a 400-watt MH bulb, once against a 400-watt HPS bulb, and once against a 600-watt HPS bulb. These trials used exactly the same conditions on both sides of the fence. The plants were cuttings taken from a single mother; the medium and grow systems were the same; and the nutrients and atmospheric conditions were kept identical. The only variable was the lamp provided. And, as usual, the results varied.
In Trial A, the clones were placed in a three-by-six-foot box that was divided evenly in half. An ebb-and-flow table on each side shared the same grow medium and reservoir. In the end, the LED lamp yielded 12% more than its counterpart, the 400-watt MH.
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]In Trial B, similar systems again pitted the UFO against a 400-watt HPS, only this time the LED side took an extra week to finish. Some concern arose over stretching, as the clone grew to touch the UFO. This resulted in a decision to increase the blue diodes in a second prototype, and it may lead to an increase in wavelength for the red diodes, according to the manufacturer. In the end, the LED side yielded 5% less than the HPS side did.
However, it was reported in Trial B that there were markedly different potencies, with the LED plant producing much more resin. Speculation exists that the shortage of wavelengths aided in this process, as abnormal stresses have been known to increase the production of resin glands.
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]Final calculations taking into consideration the extra week of flowering time on the LED side found that in terms of grams yielded per kilowatt hour (KwH) consumed, the HPS yield was one-fourth that of the LED side.
In Trial C, the grower found similarities to both previous trials. While the LED yielded less than its counterpart, this test pushed the limits of the LED by pitting it against a stronger 600-watt HPS bulb. Resin production on this Cali-O strain was up after just four weeks of flowering, but in the end, the yield was around 20% less. However, the grower did note that the amount of money saved in electric costs compared against the costs of the 600-watt HPS was almost enough to offset the profits lost on yield. An interesting side note in this trial was that the plant on the LED side needed considerably less watering than the plant on the HPS side. It is possible that this is due to lower surface temperatures in the soil medium, or because the plant wasn't driven as hard and thus drank less. [/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]
source- http://hightimes.com/microsites/led/information.inc.php
[/FONT]
