Method Seven "Classic LED Clip-Ons" change the way you see your plants and grow room using your own prescription glasses! Our Classic style clip-ons have high quality lenses with spring-loaded rubber coated metal clips that gently hold to your eyewear. This Classic style fits a wide variety of smaller or less shaped lenses. For larger lenses look at "The Aviator" Clip-on. Manufactured in Italy to our exacting standards by Carl Zeiss Vision. For use under LED lighting (see HPS Clip-on models for HPS lighting).
Method Seven makes optics for gardeners
We've been working with grow lights for over 20 years. We've tolerated the discomfort. Some of us experience night-blindness, see spots get headaches and we know a few who have gone through retina replacement surgery. Not fun.
We've solved all these problems. We can all go back into the grow and start enjoying our plants, safely and comfortably. We've got you covered for any type of lighting. Try them or ask anyone who has. You've got to see to believe.
Method Seven offers two lines of grow glasses for HPS lighting environments. Method Seven Rendition HPS delivers "Perfect Color" for the world's ultimate grow experience in the intense yellow spectrum and harsh conditions of HPS lighting. They deliver absolutely the highest available optical clarity and ability to absorb infrared (heat). These are THE best lenses for the professional working extended hours under HPS or the passionate hobbyist who simply wants the best. The “plus” silver coating option makes our glass lens even better for working in high wattage environments or crossover use outside. Plus, they just look cool :-) Our patent pending formulation is manufactured with the highest quality German durable mineral glass to provide perfect color, perfect clarity, and 100% UV protection.
Our synthetic lenses are manufactured for Method Seven by Carl Zeiss using Method Seven's unique lens technology and provide optimized color under HPS. And they provide exceptional clarity due to the high optical standards obtained by Carl Zeiss. They are very lightweight and unbreakable. We recommend our synthetic lenses to anyone with one grow light or who spends minimal time working under lights. The value of our synthetic lens makes these products great for outfitting larger crews who are working under lights but may not be making critical plant health and harvest decisions. Available either uncoated or silver coated (combining your indoor grow and outdoor lifestyle), 100% UV protection, and great value.
Both glasses provide benefits that clearly exceed the performance of all competitors.
Sunglasses are not for grow rooms!
Grow rooms have lots of light, but it's not broad spectrum. Great for plants, but not your eyes. The rods and cones in your eyes need broad spectrum light to focus, see shapes, notice movement and see color. When you wear sunglasses, you make this worse - you darken all the light, so you squint less, but you still can't see color and it's even more difficult to focus. Things look muddy. Your brain struggles to compensate. That's where fatigue and headaches come from.
Method Seven Optics filter the harsh lighting and bring balanced color to your eyes. It's like working in full daylight, naturally. you can see foliage properly, spot pests and deficiencies early and easily. your brain relaxes. No headaches, no strain, and no long-term damage. Our glasses even eliminate the strobe effect produced by most HPS ballasts. And there's no adjustment period when you walk out of the grow room. With Method Seven, you can work with accuracy, comfort and safety.
See. Believe. Your eyes are worth it!
Cheap lenses distort light as it enters your eye. Like seeing double, or slightly cross-eyed, or just hazy. Focus and clarity are compromised. You may not notice it right away, but then again you can live for several minutes with a plastic bag stretched over your head. Doesn't mean you should do it.
Method Seven Rendition lenses are made in Germany from glass, melted in six ton batches to achieve perfect clarity with your Patent Pending formulation. They are asymmetrically ground and polished and built into custom frames in Italy. This is perfection.
Our distortion free polycarbonate and nylon lens are made by Carl Zeiss. The absolute best synthetic lenses in the world. Your eyes are worth it!
Custom RX available for all spectrums.
HID lights are serious!
UV damage is cumulative, like a small sun-burn on your cornea and retina with each exposure. No one talks about UVC from the Sun because it's filtered by the upper atmosphere. Surprise! It's the most dangerous UV and is produced by most HID lights. Method Seven lenses protect from ALL harmful UVA/B/C rays. Don't risk it. You think going to the dentist is expensive and painful, try a cornea replacement. PS: for extended hours in a grow room, a visor and sunblock is also a good idea...
Method Seven technology blends incredible color balancing for each of the standard grow lighting spectrums (HPS, Metal Halide, LED, Sun) with exceptionally high quality lenses that provide the best in optical clarity. Additionally, Method Seven protection removes all harmful UV A/B rays like most others but additionally also removes harmful UVC rays which are filtered out of sunlight by the upper atmosphere, but pose a significant hazard under grow lighting.
Many growers suffer through unnecessary stress, fatigue, decreased yield, and even permanent eye injury from using sunglasses or cheaper knock-off grow room glasses. At best, even premium sunglasses attenuate (decrease) excess light in the grow room but do a horrible job of color balancing in indoor lighting environments, leading not only to discomfort and stress, but also to poor viewing and maintenance of your plants. Cheap grow room glasses do an okay job of color balancing, but typically have very poor optical quality and inadequate protection from UVC rays.
Treat yourself and your grow to Method Seven quality and style!
Q: Do Method Seven Glasses work outdoors?
A: YES! YOU CAN WEAR YOUR METHOD SEVEN'S OUTDOORS TOO! Method Seven Technology blocks and completely protects your eyes from all harmful UVA/UVB/UVC light. Our glasses are appropriate to wear outdoors under any conditions which you choose. The HPS spectrum lenses filter out less visible spectrum light than most medium and dark sunglass lenses which means they are a great choice for lower light conditions, like mountain biking in the trees or skateboarding in the early morning, but they may not be your first choice for snowboarding on a sunny day when conditions are super bright. In very bright outdoor conditions the MH Silver Plus+ lens is a fantastic outdoor lens. Made from unbreakable polycarbonate; it’s a great choice for action sports. (LED glasses are not recommended for outdoors).
Q: Why bother with grow glasses?
A: SEE. BELIEVE. While HPS, Metal Halide, and LED lighting can provide effective lighting solutions and deliver plants the light energy needed for prolific vegetative growth, they also create a hostile working environment for the human eye. Humans see best under the balanced spectrum and light levels of natural daylight conditions. Grow room lighting produces extreme conditions of excess light, very unbalanced light from unique spectrum of each artificial grow light source (HPS, LED, MH), and dangerous UV radiation from UVA/UVB/UVC.
Sunglasses help attenuate (reduce) the excess light, but do nothing to help color balance the stressful and eye fatiguing spectrums of indoor garden lighting. Cheap grow glasses offer some improvement here, but usually at a much lower optical quality than good sunglasses. Both might not protect from UVC radiation which is not a significant concern in natural sunlight due to absorption by the earth's atmosphere but which is a concern in the modern grow room.
Only Method Seven provides definitive color balancing with options for all common indoor lighting sources, exceptional clarity, and 100% UVA/UVB/UVC protection. Don’t risk using sunglasses or cheap grow room glasses!
Q: Why are Method Seven's so superior to other grow glasses?
A: SEE. BELIEVE. Grow room lighting produces extreme conditions. The hazards include excess light, very unbalanced light from the unique spectrum of each artificial grow light source (HPS, LED, MH), and dangerous UV radiation from UVA/UVB/UVC. Ballasts used by HPS and MH grow lights also creates a high frequency strobe effect in the light from these bulbs. This is not immediately obvious to the conscious mind, but is very stressful to your eyes and impedes ability to easily focus on shapes and detect movement. Working in these environments without appropriate eyewear results in eye and general fatigue, inability to correctly monitor plants, and even permanent injury to your eyes. Method Seven Optics are designed and engineered specifically and carefully for these conditions.
All Method Seven lenses are made from either premium German mineral glass or high quality synthetics manufactured to our custom standards by Italy's Carl Zeiss - world leaders in optics for over 100 years. All are asymmetrically tuned bringing distortion free focus and clarity to your eyes. Rendition glass lenses virtually eliminate the strobe effect, and Carl Zeiss synthetic lenses reduce this to physiologically low levels.
Other grow glasses attempt to color balance the extreme light spectrum of the grow room with varying degrees of success, though even those with decent light balancing typically use cheap plastic lenses with very poor clarity that distort light and are hazy or blurry. With cheap grow room glasses, your eyes and brain work overtime to compensate and you can experience fatigue, see spots, get headaches and in some cases experience damaging UV radiation.
Your eyes and health are very important. So is getting the most out of your grow. Don’t risk using sunglasses or cheap grow room glasses!
Q: Where are Method Seven glasses manufactured?
A: SANTA CRUZ INSPIRATION, GERMAN & ITALIAN CRAFTSMANSHIP. Our Rendition Perfect Color HPS mineral glass lens is made with a patent pending formulation, melted in six ton batches in a century old German factory, and ground, polished, cut and hardened in Italy.
Our synthetic lenses are made by Carl Zeiss - world leaders in optics for over 100 years. They are asymmetrically tuned bringing distortion free focus and clarity to your eyes.
Our frames are made in Italy. Final assembly of glasses into frames is also done in Italy. Packaging of glasses, carry case, wiping cloth, and boxes is done in Italy or in Santa Cruz, California.
Q: What's the story with Rendition "Perfect Color" HPS lenses?
A: COLOR BALANCING. We developed a proprietary blend of rare-earth elements that are bonded within molten glass at the molecular level. The result is canceling of a precise nanometer of light energy from the High Pressure Sodium spectrum. The lenses also selectively filter the remaining light spectrum to create the white balanced light your eyes need for maximum performance and comfort. The specific density of the glass lens also absorbs a substantial amount of infrared radiation resulting in additional comfort. Rendition Perfect Color HPS lenses provide the ultimate in color balancing, optical clarity, and protection to allow you the ultimate in comfort, visual acuity, and productivity while working with your grow.
Up your game as you as monitor plant health and correctly perceive the color of your plant leaves and the things that threaten your grow - pests, disease, rot, mildews, and mineral deficiencies and excesses - that are often hidden by the harsh lighting environment. The Rendition lens reveals color precisely enough to use a PH test strip while in the grow room. All without turning your HPS lighting off or walking your plants, or your testing equipment into daylight. (If you are the kind of person who wants to know the details, you can read about the amazing science behind in links further down this page).
OPTICAL CLARITY. Rendition Perfect Color HPS lenses are made from mineral glass which is melted in six ton batches in a century old German factory, and ground, polished, cut and hardened in Italy. They provide the ultimate in distortion free focus and clarity to your eyes.
PROTECTION. Like all Method Seven optics, Rendition lenses provide 100% protection against not only UVA and UVB radiation, but also from UVC radiation lacking in normal daylight but prevalent under grow-room lighting. Rendition lenses are also the only grow lenses in the world that eliminate virtually all of the high frequency strobe effect inherent under HPS grow lights due to the way ballast and HPS bulb product light (the strobe effect is not immediately obvious to the conscious mind, but is very stressful to your eyes and impedes ability to easily focus on shapes and detect movement, and is a huge contributor to eye fatigue when working for prolonged periods in and HPS lighted grow room).
Experience "Rendition Perfect Color" under HPS lighting - and work unconstrained in spite of that environment.
Q: Why does Method Seven offer so many options?
A: WE PROVIDE AN EXTENDED ASSORTMENT OF GLASSES BECAUSE... gardeners employ a variety of lighting types and combinations of lights to work their craft! Each type of light produces its own unique spectrum that is very different from the light levels and balanced spectrum of daytime sunlight which works best for our eyes. We make optical solutions for each of the most common of these lighting spectrums. Our glasses allow you to regain the comfort and high quality visual results you would experience in an outdoor garden environment. We also offer clip-ons for people who need prescriptions"
COLOR, CLARITY, PROTECTION
All Method Seven glasses provide outstanding Clarity, and 100% UVA/UVB/UVC protection.
Optics & Spectrum Info
NATURAL SUNLIGHT AND WHITE BALANCED LIGHT. Sunlight is composed of the full, balanced distribution of light across the spectrum of visible wavelengths from 390 to 750 nm - a magical distribution of reds, yellows, greens and blues - all the colors of the rainbow. Sunlight's even distribution of all wavelengths of light across the full spectrum produces naturally “balanced white light” (BWL). Our eyes and brain need this color balanced light to function optimally without stress, discomfort, fatigue and sometimes permanent damage. This broad spectrum of light allows us to see natural looking colors and to also easily recognize shapes and motion. The sunlight spectrum also includes invisible and dangerous UV (ultra violet) and invisible and fatiguing IR (infra red) wavelengths.
GROW ROOM LIGHTS
Each grow-room light source (HPS, MH, LED) provides a VERY imbalanced spectrum of light, with a vast majority of the light occurring in just a few wavelengths of the spectrum typical of the chemistry and physics of that light source. Plants still grow well under these imbalanced light sources and aren't negatively affected, but human eyes and brains are.
COLOR, CLARITY, PROTECTION. ONLY METHOD SEVEN DELIVERS ALL THREE.
The greater productivity, comfort, and safety, the grower needs grow glasses that filter the harsh, unbalanced light of the grow room to create BWL (balanced white light). Each lighting spectrum (HPS, LED, MH) needs its own exacting solution. Method Seven Optics have formulations to filter out the specific wavelength spikes in the spectrum of each of these common grow lightings sources, providing the wearer white balanced light within the very unbalanced environment.The lenses must do this without reducing the optical clarity of the naked eye, or the reduced optical clarity from the lenses create a different set of physiological issues for the wearer. For short term comfort and long term health, lenses must protect the eye from 100% of the harmful UVA/UVB/UVC radiation of the grow room and reduce IR exposure to the eye.
HPS lighting creates and radiates a huge amount of light. The frequent electrical excitation and decay of electrons in the sodium atoms generates the vast majority of total light output at a specific "yellow" wavelength around 590 nanometers. This wavelength is a very suitable energy source for plants to use for photosynthesis and growth, and light and ballast costs have traditionally been low. HPS lights use considerable electricity and produce considerable excess heat. The yellow spike of HPS lights is especially challenging to our eyes due to the poor spectrum, the exceeding poor yellow / blue ratio of the light that impacts the functioning of the rods and cones in our eyes, and the high frequency "strobe effect" from the ballasts (more details elsewhere on this page).
Unlike most HPS lamps, the light spectrum produced by commercially available LED equipment varies between manufacturers and is dependent on the combinations of diode, amperage, magnification and a host of design considerations. The best LED spectrums for optimum plant growth typically produce a distinctive magenta color appearance.
MH bulbs produce light that's strongest at the blue end of the spectrum resulting in a stark, bright white light. MH bulbs tend to be very bright, and glasses need to appropriately attenuate (decrease) total light to the eye in addition to providing color balanced light and 100% UVA/UVB/UVC protection.
Our eyes evolved to function best under daytime sunlight with its full, balanced distribution of light across the full spectrum of red, yellow, green and blue wavelengths from 390 to 750 nm. Our eyes and brain need this color balanced light to function optimally without stress, discomfort, fatigue and sometimes permanent damage. This broad spectrum of light allows us to see natural looking colors and to also easily recognize shapes and motion.
"BALANCED WHITE LIGHT"
When reproducing the full sunlight spectrum artificially, the spectrum is called "balanced white light" (BWL). Each type of grow light (HPS, LED, MH) produces a spectrum very far from white balanced light. Photographers learned long ago that the color of light on an object changed the way a camera/film registers the color of the object, just as the color of light on an object changes the way our eyes perceive the color of that object . With the advent of modern light metering and photo processing software, photos can be white balanced after the fact. Photographers have created a process where they photograph a specific color of white paper at the same time they take a photograph, and later adjust the finished photographs (using photo software like Photoshop) until that white paper looks the correct shade of white again. This allows the other objects photographed to appear the correct color too.
When looking at something under a spectrum other than balanced white light, your eyes work hard and partially color correct what they see. The more unbalanced the spectrum, the harder your eyes work and the less they can successfully compensate. Look at a sheet of white paper under grow lights, and you will notice that it doesn't look even close to white, instead you see the unbalanced color spikes of the grow room light source. Your eyes can't come close to compensating for the extreme lighting environment of indoor grow lights. Look at that same piece of paper with Method Seven glasses, and see the exact shade of white you see outdoors under natural sunlight! For more technical information about color balancing, eye physiology and specific Method Seven products, see the "Color Perception & M7 Color Balancing" section lower on this page.
COLOR, CLARITY, PROTECTION
Light balancing is only one of the challenges for optical products for the indoor grower. Only Method Seven delivers products for different light source spectrums with state of the art color balancing, optical clarity, and 100% UVA/UVB/UVC protection.
Method Seven Rendition Perfect Color HPS lenses are made from high grade mineral glass. The elements added to the glass are atomically bonded into the crystalline structure. There are no emulsions or dyes to interfere with optical clarity. Method Seven's synthetic lenses likewise provide exceptional optical clarity. These lenses were developed in partnership with Carl Zeiss, a 100 year old Italian lens manufacturer well known for the optical quality of their lenses.
The best glass lens sunglasses on the market match the optical clarity of the Rendition mineral glass lenses (but don't color balance for indoor growing, and may not protect from UVC radiation). Less expensive sunglasses and cheap grow glasses have poor optical quality and contribute to eye stress and fatigue.
Eye Protection & safety standards:
PROTECT YOUR EYES! Find yourself constantly squinting in the grow room? Over time constant exposure to high levels of UV and infrared radiation leads to irreparable eye damage. Loss of color perception, cataracts, and the destruction of your night vision are possible. All of our lenses blocks all harmful invisible wavelengths (UVA, UVB, UVC and Infrared). Your plants require these invisible wavelengths to flourish. Your eyes certainly don’t.
But that's not the whole story. Cones and rods within your eyes control the eyes ability to focus and function best at light wavelengths very different from the indoor grow environment. New science proves that the eyes extra effort to focus and correct for excess yellow from HPS lights causes a host of eye strain and health problems. Rendition lenses balance the light in a way that allows your eyes, brain, and body to function correctly again. This results in drastically less mental strain and fatigue. Less fatigue equals better decision-making and a pleasant experience in your grow room.
Method Seven glasses meet or exceed international safety tests for optical quality, clarity, breakage and UV protection.
HPS lighting story:
High Pressure Sodium (HPS) lighting has long offered a cost effective solution for some industrial applications such as the lighting of warehouses and for Grow Room lighting. HPS lighting also creates visual problems for people working within its environment. The details of these visual problems are discussed in our eye physiology section. But in general, HPS lighting causes significant decrease in color perception and ability to focus on shapes and motion. The "strobe" light effect caused by the high frequency, cyclical variation in power from the HPS ballast to the bulb causes a similar high frequency variation in light intensity which also has negative impact on our eye's ability to function comfortably and effectively under these lights.
HPS lighting creates and radiates a huge amount of light. The frequent electrical excitation and decay of electrons in the sodium atoms generates the vast majority of total light output at a specific "yellow" wavelength around 590 nanometers. This wavelength is a very suitable energy source for plants to use for photosynthesis and growth.
This same concentration of yellow light makes it difficult for an individual to see properly. Humans see best in natural sunlight, or in “Balanced White Light” (BWL). BWL light, like natural sunlight, covers the entire visible spectrum of 390 to 750 nm. This broad spectrum of light allows us to see natural looking colors and to also easily recognize shapes and motion. Under HPS lighting our eyes are saturated with yellow light and we are unable to recognize any other colors.
Human eyes also require a certain ratio of blue light (around 505 nm) to yellow light (around 555 nm) to be able to recognize shapes and to detect motion. HPS lights provide some of this blue light, but in far to low a ratio compared to the prevalent yellows, and this profoundly degrades our ability to focus. This point will be explained further in the discussion of “rods” and “cones.”
COLOR, CLARITY, PROTECTION. METHOD SEVEN DELIVERS!
Others can try to copy but fall short: Method Seven developed the world's first HPS grow glasses and offers HPS glasses with patent pending Rendition Perfect Color HPS technology with German mineral glass or high optical quality synthetic lenses developed with Carl Zeiss (a world leader in high quality optical lens production). Only Method Seven delivers finished glasses of incomparable style and quality and meets your needs for Color, Clarity, Protection!
LED lighting story:
LED (light emitting diodes) grow lights are a relative newcomer as source for indoor horticultural purposes. They are the up-and-coming state of the art. Initial light / fixture costs tend to be higher than HPS and MH, but ... these costs can often be recouped quickly due to much lower energy consumption per lumen, less excess heat in the grow room, and the very long lift of bulbs. Unlike most HPS and MH lamps, the light spectrum produced by commercially available LED equipment varies between manufacturers and is dependent on the combinations of diode, amperage, magnification and a host of design considerations. The best LED spectrums for optimum plant growth typically produce a distinctive magenta color appearance. Method Seven chose Black Dog LED, considered an LED market leader, as the benchmark spectrum for design of the LED specific lens formulation.
The Method Seven LED Optics will balance color optimally under Black Dog LED lights, but has been tested with a number of other commercial LED lights and functions exceptionally well with all other brands tested to date. Color correction might vary slightly with alternative equipment (imperceptible in most cases) but in all cases Method Seven Optics will protect against all UV damaging ray regardless of LED brand.
METHOD SEVEN OFFERS THE WORLD'S FIRST AND ONLY LED BALANCING GROW LIGHTS.
Color, Clarity, Protection. Method Seven delivers!
Metal Halide lighting story:
Historically, in contrast to HPS lighting, Metal Halide lamps have had a higher initial cost but are typically slightly more efficient, produce less (but still considerable) heat, and have a broader, more diverse spectrum of light for plants. MH bulbs produce light that's strongest at the blue end of the spectrum resulting in a stark, bright white light. MH lighting may prove less difficult for the human eye than HPS, but still causes considerable eye strain and great risk from UV radiation. MH bulbs tend to be very bright, and glasses need to appropriately attenuate (decrease) total light to the eye in addition to providing color balanced light and 100% UVA/UVB/UVC protection.
METHOD SEVEN OFFERS THE WORLD'S FIRST AND ONLY MH BALANCING GROW LIGHTS.
Color, Clarity, Protection. Method Seven delivers!
Really technical info if you really want to know ...eye physiology & M7 optics
Color Perception & M7 Color Balancing:
We can evaluate how close we are to BWL conditions by using two well-known methods.
In the first method, we evaluate the amount of red, blue, and green light reflected off of a “middle grey” target, better known as a photographic 18% grey card. Under BWL conditions, an equal amount of red, blue and green light is reflected off of this target.
We can also measure color using a Kelvin Color Meter that measures the visual “temperature” of the light.
MEASUREMENT OF COLOR BALANCE USING A MIDDLE GREY TARGET
Method Seven uses a Canon 5D Mark II (CAMERA) with a 100mm 2.8 macro L series lens (LENS) and an X-Rite Digital Color chart to confirm color balance. Each color block within the X-Rite Color chart has a known intensity of Red, Green, and Blue (RGB).
Digital color may be determined in Photoshop, by how much of each of the RGB values register from 0 to 255. For example the color black registers as R=0, B=0, G=0. Conversely, white registers as R=255, B=255, G=255.
When reflecting BWL, the middle grey target registers in Photoshop as any combination of equal value such R=160 G=160 B=160. Under HPS conditions, this same target registers as R=214 G=138 B=0, which we see as a harsh yellowish to reddish color.
The blue outline denotes the middle grey color block.
COLOR CHART BALANCED WHITE LIGHT CONDITIONS
(This is how you see a color palette in sunlight)
COLOR CHART HPS LIGHTING CONDITIONS
(This is how you see the same color palette in typical HPS lighting)
Place the Method Seven Rendition lens in front of the camera, and take a photo of the same grey target, in the same HPS environment, and the color registers as R=149 G=145 B=142. This result is much closer to the established middle grey value of R=160, G=160, and B=160.
COLOR CHART HPS LIGHTING WITH METHOD SEVEN RENDITION LENS
(This is how you see the color palette in HPS lighting looking through Rendition Lenses!!!)
COLOR CHART HPS LIGHTING WITH METHOD SEVEN FISSION POLYCARBONATE LENS
(This is how you see the color palette in HPS lighting looking through Fission Lenses!)
The test results for each lens type, and a calculation of the percentage of color balance, is shown below.
MIDDLE GREY TEST RESULTS
NUMERIC EVALUATION OF RESULTS
The variance in RGB values is calculated using the standard deviation of the RGB values. Then, an estimation of the percentage of unbalance is obtained by taking the ratio of the standard deviation of the measurements divided by the average of the measurements. The percentage of balance is then calculated by subtracting the percentage of unbalance from 100 percent.
The Method Seven Rendition Lens brings color balance closer to the way the human eye would see the same middle grey color under BWL.
The Method Seven Fission polycarbonate lens, likewise, improves color balance. In comparison, sunglasses further degrade color balance, because by design sunglasses filter out more light around the wavelength of blue light, than light around the wavelength of yellow light. This is the opposite of what is required to better see natural looking colors in an HPS lighting environment.
MEASUREMENT OF COLOR BALANCE USING A KELVIN METER
In the 1980s the British physicist William Kelvin noticed that a block of carbon gave off different color hues based on the temperature of the block. At lower temperatures of about 1500 degrees Kelvin, the carbon emitted a red glow. As the temperatures increased the colors became more orange, then yellow, green, and eventually blue. The relationship of color to the temperature of that block of carbon is now well known. Today, you can purchase a Kelvin color meter that will instantly characterize the hue being measured and provide what is now called a “Kelvin temperature”, that corresponds with that hue.
The morning sun registers as 5000 degrees Kelvin, a target often given to BWL. HPS lighting registers as 2680 degrees Kelvin. The human eye can detect color fairly well, even under indoor lighting conditions of about 4000 degrees Kelvin. However under intense lighting at 2680 degrees Kelvin, all we see is yellow or orange.
In the following table, we show the measurements of HPS lighting, as seen through the various lenses as measured by a Kenko KCM-3100 Kelvin color meter.
KELVIN TEMPERATURE MEASUREMENTS
The Rendition lens balances the light spectrum to provide a Kelvin temperature that is closer to that of BWL, and closer to the optimal color of indoor lighting. Likewise, the Fission lens positively balances the light spectrum. Both sunglass lenses bring the Kelvin temperature away from BWL conditions, again because they remove more blue than yellow light.
BOTTOM LINE REGARDING COLOR
It’s impossible to recognize the colors of your plants with the naked eye in an HPS environment because everything you see appears to be yellow. Sunglasses do not help. The Rendition and the Fission lenses, however, allow you to see the natural looking colors of your Grow Room plants.
Focus, Strobe Effect, Rods & Cones ...
It’s difficult to work within a Grow Room, or a warehouse, that is saturated with light from an HPS source. Although you may not know why, you instantly feel uncomfortable when entering such an environment. in the 1980’s, industrial engineers were becoming wary of the downsides of HPS lighting. People working in warehouses, lit by HPS, were having difficulty seeing well enough to do their jobs, and in some cases were getting headaches and becoming ill. As Industrial engineers and scientist began to investigate these vision problems they became more aware of the role that cones and rods play in our ability to see well.
CONES AND RODS
In the early 1990’s Dr. Sam Berman and his colleagues at the Lawrence Berkeley National Laboratory in Berkley, California, figured out why workers were getting headaches and having problems focusing when working under HPS lighting conditions.
HPS lighting gained popularity because of the large amounts of lumens of light provided for a given amount of power. This light, however, is concentrated within a very narrow spectrum, which we see as yellow. Unfortunately, humans need a broad spectrum of colors to see properly.
There are two kinds of photoreceptor cells in human eyes. We have cones and rods. There are about 7 million cones in the average eye, and these cones are located mostly in the center of the back of the eye. Cones respond best to light having a wavelength centered around 555 nanometers, the wavelength of yellow to orange light.
There are around 120 million rods in the average eye, and these rods are spread out throughout the periphery of the back of our eyes. Our rods respond best to light that has a wavelength centered around 505 nanometers, or the wavelength of blue light.
Although rods are normally associated with night vision, Dr. Berman discovered rods are also vitally important for proper daytime vision. More specifically, while our cones help us to detect color, rods are needed to detect movement and shapes.
Daylight, and most indoor lighting, provide a sufficiently broad spectrum of light to adequately excite the rods and the cones in our eyes. HPS lighting, however, provides such a narrow bandwidth of light, that our cones are over stimulated, while at the same time our rods are understimulated.
Dr. Berman discovered that despite the intensity of the yellow light of the HPS lighting environment, workers were not getting enough light near the blue portion of the light spectrum to properly detect movement or shapes.
SCOTOPIC AND PHOTOPIC LIGHT
Our eyes do a remarkable job of adjusting for the intensity of light in our environment. Our pupils enlarge or get smaller to allow the best possible amount of light to our rods and cones to maximize our vision. Once our eyes adjust to the intrinsic light level, then it is up to our rods and cones to help our brains see color, movement, and shapes.
Dr. Berman and his associates determined that the ratio of light centered around the blue part of the light spectrum (referred to as scotopic light) to light centered around the yellow part of the light spectrum (referred to as photopic light) was very important. The ratio of scotopic to photopic light (S/P) of natural sunlight is 2.5. Most good indoor lighting has an S/P ratio of about 2.0. With a ratio of 2.0 humans can easily recognize shapes and movement as well as natural looking colors.
With this as a background, one can understand why Method Seven lenses offer relief in the HPS lighting environment. Both Rendition and the Fission lenses increase the ratio of scotopic light to photopic light, allowing our eyes to more easily focus on shapes and movement.
Sunglasses make the problem worse, because they filter out more scotopic light than photopic light, and therefore actually lower the S/P ratio.
Looking for an objective measurement, Method Seven used a SolarLight SnP Meter, model SL3101, to measure the photopic and scotopic light under various conditions. These test results are shown below as an S/P ratio.
S/P TEST RESULTS
The Rendition and Fission lenses increase the percentage of scotopic light making it easier to recognize shapes and to detect motion, therefore making it easier to focus in the Grow Room environment. The Rendition lens moves the user to 70 percent, and the Fission lens to 50 percent, of a more ideal ratio.
THE STROBE EFFECT
Another phenomenon that adversely affects someone working under HPS lighting conditions is the ‘strobe effect’ of all of the lights slightly dimming and slightly getting brighter as the AC voltage cycles. You will not be consciously aware of this phenomenon because our brain compensates for this strobe light effect. Still, this strobe effect causes some people to get headaches or otherwise become ill.
If you use a video camera in a Grow Room you will likely see lines running through your video shot. These lines are from the strobing effect of the HPS lighting. If you place a Rendition lens in front of your video the lines will go away.
The Rendition lens filters out the strobe effect and the Fission lens significantly reduce the strobe effect. They do so by decreasing the intensity of the yellow light spectrum that is being modulating by the AC voltage cycle.
Sunglasses minimally reduce the strobe effect.
|Dimensional/Billable Weight (lbs)||2|
|Country of Manufacture||Italy|
|Free Shipping||FREE Ground Shipping!|
|Model||Method Seven Classic LED Clip-On Glasses|
|Manufacturer's Suggested Retail Price||$59.00|