Dec 22, 12
For this week’s issue of Light Post, we’ve collected some excellent lighting stories, from a Dallas-area Christmas light tour, to some last-minute holiday lighting tips, and even a scoop on how LED lights are helping astronauts sleep. So, post up in your favorite spot and enjoy Light Post.
Farmers Branch Offering Tour of Lights
If you live in the Dallas/Fort Worth Metroplex, check out the Tour of Lights in Farmers Branch. This drive-through event features hundreds of thousands of Christmas lights and displays. To get there from the intersection of Interstate 35E at Valley View Lane, follow the candy cane signs down William Dodson Parkway to Farmers Branch City Hall, through the DART station area and to the Farmers Branch Historical Park. What makes this event even sweeter is that it’s FREE. The Tour of Lights runs through December 1 to New Year’s Eve.
Holiday Lighting Safety Tips
These tips come all the from Wayne County, NY, but lighting safety tips are universal and will ensure you have a safe holiday season.
- Make sure you inspect your lights each year before putting them on the house. Look for worn or frayed receptacles, cords, and loose connections. If you find anything out of place, replace your lights with new ones from 1000Bulbs.com.
- For those who’ve seen ‘Christmas Vacation’, you know that electrical cords and cats don’t mix. Well, neither do toddlers and electrical cords. Make sure cords are out of reach of your four-legged friends and the kiddos.
- The only hassle with live trees is keeping up with all the stray needles and refilling the water when your cats drink out of the tree holder. Having a live tree takes a few more safety steps. Cut the base of the tree at a 45-degree angle to allow water absorption. Also, use mini lights as they produce much less heat than regular lights and reduce the drying effect on the tree. Pesky, water-drinking cats aside, your tree will drink anywhere from a quart to a gallon of water each day, so refilling the water prevents the tree from drying out.
- All of these safety tips are no replacement for checking and replacing the batteries in your smoke detectors.
LED Lights to Combat Astronaut Insomnia
Apparently sleep is tough to come by on the International Space Station. NASA flight surgeon Smith Johnston explains why: “The station is noisy, carbon dioxide is high, and you don’t have a shower (seriously?).” This is why NASA is spending $11.2 million on switching out the space station’s fluorescent lights for color-alternating LEDs. The LEDs will alternate from blue, white, and red, based upon the time of day. NASA says it plans to have the switchover completed by 2016.
LED Lighting Options Help Christmas Displays Go Green
One year, I put about 7,000 lights on my parents’ house. They liked the lights, until they got their electric bill. However, there are a lot of money-saving options like LED mini lights. LEDs are the most efficient lights you can buy, and will save you a ton in electricity costs. Powering 600 incandescent lights for six hours a day will cost about $80, while the same number of LED lights will cost only $7.
Jun 29, 12
It’s a long accepted fact that production of the hormone responsible for sleepiness, melatonin, can be suppressed by light. The pineal gland uses the presence of light to determine when to release and suppress the hormone, setting our “internal clock” to a cycle of wakefulness and sleep, also known as a circadian rhythm. Not surprisingly, the large amount of artificial light we encounter in the modern world can have a negative effect on this cycle by suppressing melatonin production even at night. However, recent studies suggest that not just the amount of light, but also the color of the light we encounter may affect our sleep cycles.
A 2005 study conducted by researchers at Kyushu University in Japan suggests that exposure to high color temperature light immediately preceding bedtime reduces the length of stage 4 sleep. In the study, the researchers exposed different subjects to 3000K, 5000K, and 6700K light sources for 6 hours before going to sleep. Researchers monitored the subjects’ sleep patterns and came to this conclusion:
Given that the S4-sleep period is important for sleep quality, our findings suggest that light sources of higher color temperatures may reduce sleep quality compared with those of lower color temperatures.
Other studies by the University of Basel in Switzerland and the University of Connecticut found similar results.
Though these findings are not yet accepted scientific fact, it’s worth noting that manufacturers have already started to create products with these ideas in mind. Philips, for example, produces an entire line of “Wake-Up Lights” that use increasing light intensity and color temperature to wake you from sleep, a method that is marketed as a more natural alternative to alarm clocks. The computer program and smartphone app f.lux reduces the color temperature of screens for less obtrusive nighttime reading. On the flip side, companies have long used “full spectrum” office lighting to increase alertness and productivity, assuming that if high color temperature lighting discourages sleep, it must also encourage wakefulness.
While the scientific community works this all out, what can you do now to improve your sleep? Start with what we do know: Bright light of any color temperature suppresses the production of melatonin, so limit the use of artificial light in the hours preceding sleep. This is easy to do with dimmers, 3-way bulbs, and even low wattage bulbs. Second, conduct your own study: If you currently use high color temperature bulbs and have difficulty sleeping, switch them out for soft white or warm white bulbs and see if you notice a difference.
If you try these ideas out, we’re curious about the results. Does color temperature have any effect on your sleep? Let us know in the comments, or drop us a line on Facebook, Twitter, or Google+.
Jun 08, 12
Ah…summertime. Warm weather, pool parties, barbecues, and bugs. Lots and lots of bugs. Few things can turn a summer day into utter misery faster than a swarm of flying insects. You’ve tried greasy bug spray, citronella candles, Tiki torches, maybe even blowtorches. So we can imagine your surprise when you saw a yellow-colored “bug light bulb” at your local hardware store. Could it be true? Could screwing in a light bulb solve your bug problems for good?
To answer that question, let’s start by clearing up some myths about yellow incandescent bug lights and their energy-saving cousin, compact fluorescent bug lights. Bug lights do not kill bugs (you’ll need a bug zapper or Paraclipse fly trap for that), nor do bug lights repel bugs. Bug lights simply attract fewer bugs than other light bulbs. In short, a bug light will not magically solve your bug problem, but it will make you and your home less visible to most flying insects.
As discussed in a past article, light is divided into multiple wavelengths, measured in nanometers (nm), as you can see in the graph below. The human eye can only perceive a small band of wavelengths in the light spectrum, from about 390 to 750 nm. Insects perceive a similarly small band of the light spectrum, though their band of vision is shifted further to the “right” of the spectrum than ours. In fact, any wavelength higher than about 650 nm is virtually invisible to most flying insects.
Image courtesy of Chemistryland.com
So why are bug lights yellow? Wavelength and color temperature have an inverse relationship, which you can also see in the graph. As the wavelength of a light source decreases, its color temperature increases (as according to Wien’s displacement law). Low color temperatures are red-yellow and exhibit a long wavelength, while high color temperatures are blue-violet and exhibit a short wavelength. By coloring a bulb yellow, then, the manufacturer has decreased the color temperature and in doing so increased the wavelength into a spectrum unseen by insects.
That’s the science of how bug light lights work, but the larger question is whether they are effective. From personal experience, I can say yes, they are. However, bug lights are not a panacea for all your bug problems. This is for a couple reasons. One is that not all insects are the same; different bugs see slightly different wavelengths. Second, no light source is made up of one, pure wavelength. Even an apparently yellow light may exhibit some shorter (and bluer) wavelengths that insects may still see.
To get the most out of your bug light, remember this: The bugs aren’t there because they like the light; they’re there because they like the smaller (and tastier) bugs that buzz around the light. If these smaller bugs sense any light whatsoever, it won’t be long before they buzz their way to bask in it. And once the small bugs are there, it won’t be long before the bigger bugs follow. Once that happens, you have a bug party on your hands, light or no light. The best thing to do to avoid a swarm of bugs is to turn the light off when you don’t need it.
May 25, 12
The following are excerpts from actual reviews on 1000Bulbs.com. What do they have in common? They’re all from reviews of 130 volt light bulbs.
“…even though the watt ratings are the same…the new ones aren’t as bright as the old ones.”
“The low output also makes the the color of the light very yellow…”
“…for 300 watts I thought it would be brighter.”
These customers, and several others, have a fundamental misunderstanding of 130 volt light bulbs. That’s not their fault, however; it’s ours. So let me try to clear up this issue once and for all.
As discussed briefly in an earlier article, the short, technical version goes like this: 130 volt Halogen and incandescent light bulbs are manufactured with a thick filament designed to withstand a theoretical 130 volts. I say “theoretical” because almost all homes in the US operate on only 110-120 volts. The thicker filament in a 130 volt bulb, when operated on typical 110-120 line voltage, provides less resistance to the electrical current flowing through the filament. As a result, the bulb burns cooler, uses less energy (watts), and lasts longer; however, as a trade-off, the bulb is also slightly dimmer and has a lower (more yellow) color temperature.
Understanding Voltage, Amps & Watts: “Hose Theory”
To understand this phenomenon, an analogy is useful. Think of a garden hose. When you turn on the tap to just a trickle, water flows freely through the hose without resistance. As you turn the tap more, you force a larger volume of water through the hose, which is met by a small amount of resistance from the hose. Now turn the tap to its highest setting. Instead of trickling from the end of the hose, water now sprays across your lawn and into the leather interior of your neighbor’s new convertible.
Because the hose is relatively small, it provides a lot of resistance to the more voluminous water flow, which causes pressure to build inside the hose. The increased pressure in the hose propels the water several feet instead of flowing with the mere trickle you saw when you had the tap at a lower setting. To take this concept further, imagine you continued to increase the volume of water flowing through the hose by attaching it to a fire hydrant (assuming such a thing was possible). At that point, the water pressure would become so intense it would weaken the hose, eventually causing it to rupture.
Maybe that’s a dramatic example, but the thin tungsten filament of a light bulb is not unlike a water hose. In the case of electricity, however, the volume of water is electrical current and the water pressure is voltage. With a 60 watt light bulb, for example, you are forcing 0.5 amp of electrical current (the “water”) through the filament (the “hose”) with 120 volts of pressure. The current meets the resistance of the filament, causing the filament to become hot and glow. Over time, just as with the water hose, this stress will cause the filament to break, making the bulb “burn out.”
130 Volt Bulbs Save Energy & Last Longer
To prolong the life of the bulb, you could lower the volume (amps) or the pressure (voltage). This is the approach taken by old rheostat dimmers.
Voltage Decrease & Bulb Efficiency
However, you could also use a bulb with a thicker filament (a bigger hose), that places less resistance on the current so that it flows more easily. This method, as stated before, is the approach taken by the 130 volt bulb. Because the current moving through the thicker filament meets less resistance, it requires less energy to produce light. The more freely moving current also does not make the filament as hot so that the color temperature of the light is also lower.
As the table to the right shows (from Jack L. Lindsey’s Applied Illumination Engineering), the trade-off is a very good one, too. A very small decrease in voltage and lumens leads to a huge increase in life and a considerable decrease in energy usage (watts). Lowering the voltage only 8%, for example, leads to a 300% increase in life and nearly 15% decrease in energy usage with only a 25% loss in light output!
Now back to the original question: Why buy 130 volt light bulbs? The answer is simple. Buy 130 volt bulbs when you want to save energy, change your bulbs less often, and don’t mind slightly lower light output and warmer color temperature.
May 11, 12
Every light source has a distinct character, from the warm, dim glow of a candle to the blue, bright beam of a street light. Brightness, measured in lumens, is one part of that character; the other part is color temperature. Measured in degrees Kelvin, color temperature is not the ambient hot/cold temperature of our surroundings. In fact, the Kelvin scale goes backwards: The higher the color temperature, the cooler light gets, and the lower the color temperature, the warmer light gets.
Warm Color Temperatures (2000K to 3500K)
Lighted Makeup Mirror
Most homes look best in warm-toned light. This is for several reasons, but the first one is a home’s color scheme. People tend to decorate homes in warm earth tones—reds, oranges, and yellows—which warm light enhances. In addition, people tend to look better in warm light. If your grandmother had a lighting makeup mirror with adjustments based on “office,” “home,” and “evening” lighting, you may remember that you looked a lot better in “home” and “evening” modes than “office” mode. That’s because (you guessed it!) those modes had lower color temperatures than “office” mode.
Cool Color Temperatures (4000K to 4500K)
While warm color temperatures are the residential standard, some people prefer higher or “cooler” color temperatures. Because of their neutral tone, it’s common to see color temperatures of 4000K or higher used as task lighting in offices. Moreover, people often perceive higher color temperatures to be brighter than warm temperatures, while others feel cooler light looks “cleaner.” Finally, higher color temperatures can enhance homes with cooler color schemes, especially those with a lot of blues and whites.
Full Spectrum Color Temperatures (5000K to 6500K)
Less common are very high color temperatures, often referred to as “full spectrum” or “daylight.” Color temperatures of 5000K to 6500K approximate the color of light outdoors on a bright, sunny day. The cast of the light can be a very pronounced blue and can seem harsh to some people. It’s unlikely to see color temperatures of this range in homes, though there is a trend of installing “full spectrum” bulbs in offices as they are sometimes associated with higher productivity.
Making a Decision
There’s nothing that can sour your opinion of CFL or LED lighting like buying a 4000K or 5000K bulb when you meant to buy a 2700K bulb, or vice-versa. When you buy a new, energy efficient bulb, keep your application and color scheme in mind and make sure to buy the bulb with a color temperature to match. For more information, check out this color temperature chart on our website.
So do you prefer warm or cool color temperatures in your home? Have you ever mistakenly bought a bulb of the wrong color temperature? Share your thoughts and experiences in the comments section below or contact us on Facebook, Twitter, or Google+.