sitelights
09-14-2004, 12:29 PM
First full disclosure: the two free samples (one white, one green) were sent to me at my request; there was also no charge to me for USPS mail They were nicely packed in ZipLok bags and included two sets of no name (unmarked) insulated, blue, belled butt splices that appear to accept 14-16 gauge wire. The LEDs are available in seven colors.
Second full disclosure: I am not now nor ever have been a proponent of color in outdoor lighting. Clearly I come to this product with a bias so I will not make any aesthetic judgements. I happen to be a purist in the matter of hued outdoor lighting but that is my personal limitation. I admit however that I have used colored gels in stage lighting to set mood. Here the light source is visible which is counter to my design sensibilites. EasyTron's web site has clear images of lighting effects achieved.
The effect of these colored LED light sources is not my particular cup of hemlock...strike that and insert "tea"...perhaps I am a color snob. My 12-year old daughter thought they were "cute" but that would be to me "...damning with faint praise..." (Shakespeare?...where?). In any case they work as intended, will probably last forever and consume very little energy. In my opinion LEDs are still under development but if you wait for improvements (particularly in the development of bright, white, low energy light sources) you might never use them since they incremently improve while you are reading this. LEDs are probably (stay tuned) the light source of the future; however, improvements in the efficacy of incandescent sources (picture a gas lantern's mantle that glows with electrical current instead of combustion) may eventually illuminate me while I eat those words. (search "incandescent")
But then this is a product review so let's get to the product.
The attached image looks a bit cluttered so I will explain. Upper center and proceeding clockwise: two EasyTron LED clusters, a line dimmer, a digital volt meter, a light meter and a jumble of wires. Note that the area toward the bottom center of the image is lighted from a 60w articulated work light about two feet above the surface. The LEDs were too bright to image in the dark. The LED clusters consist of three LEDs attached to ten feet of 18 gauge solid core copper wire. Since the wire is solid it will remain the way you bend it. There is also a separate six inch length of coated wire securely attached just below the LEDs to use like a twist tie for mounting to, for example, a branch of less than 1.5 inches in diameter. The attachments are done skillfully by hand not by a machine and I found it impossible to disassemble a cluster without destroying it.
A simple test was devised to determine how well the LEDs performed under varying voltages. The input to a 12v transformer was controlled by the dimmer and the output was connected to a 20w bi-pin xenon lamp (for reference) and an ordinary digital volt meter. The leads for the LED clusters (alligator clips) are ganged. This allows complete control of the voltage to the LEDs and the digital meter measuring the voltage here reads 10.55 volts. In the image light the meter has been turned off so there is no numerical display; the light sensor (white disk) is on the same face as the readout so it is not possible to show LED output as footcandles (FC) so you will have to trust me.
The light meter sensor is held above the white (blue-white) LED cluster so as to lightly touch the disk. By metering voltage and light output a range of voltage and its effect on the brightness of the LED can be compared. These LEDs are encapsulated within clear material shaped to achieve a tightly focused very bright spot (you would not want to stare at it); the light falls off dramatically when viewed other than straight on. This is clearly seen in the attached image. As a reference a 20w lamp was wired into the transformer output and the FC level of the 20w lamp measured under identical conditions.
Interestingly (at least to me) the LEDs, to the eye, do not vary much with current (if you know why, tell me); conversely the 20w lamp dimming in a linear manner as a function of the voltage produces results more pronounced to the eye. The quantifiable results obtained are shown in the paragraphs below as a ratio i.e. volts/footcandles.
The white LED cluster: 3.38/37.3, 9.08/197, 10.55/296 and 12.55/613.
The 20w xenon bi-pin lamp: 10.55/460 and 12.55/1225. Daylight on this overcast day: 1790.
Of course what was being measured was not "illumination" but rather "luminosity". I covered the distinction (search "luminous") in an earlier post. I applaud EasyTron for their candor on this point in their web site and in their print materials.
This is an emerging product that could be much more efficiently (and economically) produced off-shore in the lands of rice bowl labor; it is only a matter of time until this innovative product is cloned without royalty payments at a killingly low price. It seems that we export technology and import goods; pretty soon we will be importing both and will live by selling lottery tickets to eachother. As usual, I have informed the principals of EasyTron of this review so that they may correct any of my errors; however I need to be convinced.
Second full disclosure: I am not now nor ever have been a proponent of color in outdoor lighting. Clearly I come to this product with a bias so I will not make any aesthetic judgements. I happen to be a purist in the matter of hued outdoor lighting but that is my personal limitation. I admit however that I have used colored gels in stage lighting to set mood. Here the light source is visible which is counter to my design sensibilites. EasyTron's web site has clear images of lighting effects achieved.
The effect of these colored LED light sources is not my particular cup of hemlock...strike that and insert "tea"...perhaps I am a color snob. My 12-year old daughter thought they were "cute" but that would be to me "...damning with faint praise..." (Shakespeare?...where?). In any case they work as intended, will probably last forever and consume very little energy. In my opinion LEDs are still under development but if you wait for improvements (particularly in the development of bright, white, low energy light sources) you might never use them since they incremently improve while you are reading this. LEDs are probably (stay tuned) the light source of the future; however, improvements in the efficacy of incandescent sources (picture a gas lantern's mantle that glows with electrical current instead of combustion) may eventually illuminate me while I eat those words. (search "incandescent")
But then this is a product review so let's get to the product.
The attached image looks a bit cluttered so I will explain. Upper center and proceeding clockwise: two EasyTron LED clusters, a line dimmer, a digital volt meter, a light meter and a jumble of wires. Note that the area toward the bottom center of the image is lighted from a 60w articulated work light about two feet above the surface. The LEDs were too bright to image in the dark. The LED clusters consist of three LEDs attached to ten feet of 18 gauge solid core copper wire. Since the wire is solid it will remain the way you bend it. There is also a separate six inch length of coated wire securely attached just below the LEDs to use like a twist tie for mounting to, for example, a branch of less than 1.5 inches in diameter. The attachments are done skillfully by hand not by a machine and I found it impossible to disassemble a cluster without destroying it.
A simple test was devised to determine how well the LEDs performed under varying voltages. The input to a 12v transformer was controlled by the dimmer and the output was connected to a 20w bi-pin xenon lamp (for reference) and an ordinary digital volt meter. The leads for the LED clusters (alligator clips) are ganged. This allows complete control of the voltage to the LEDs and the digital meter measuring the voltage here reads 10.55 volts. In the image light the meter has been turned off so there is no numerical display; the light sensor (white disk) is on the same face as the readout so it is not possible to show LED output as footcandles (FC) so you will have to trust me.
The light meter sensor is held above the white (blue-white) LED cluster so as to lightly touch the disk. By metering voltage and light output a range of voltage and its effect on the brightness of the LED can be compared. These LEDs are encapsulated within clear material shaped to achieve a tightly focused very bright spot (you would not want to stare at it); the light falls off dramatically when viewed other than straight on. This is clearly seen in the attached image. As a reference a 20w lamp was wired into the transformer output and the FC level of the 20w lamp measured under identical conditions.
Interestingly (at least to me) the LEDs, to the eye, do not vary much with current (if you know why, tell me); conversely the 20w lamp dimming in a linear manner as a function of the voltage produces results more pronounced to the eye. The quantifiable results obtained are shown in the paragraphs below as a ratio i.e. volts/footcandles.
The white LED cluster: 3.38/37.3, 9.08/197, 10.55/296 and 12.55/613.
The 20w xenon bi-pin lamp: 10.55/460 and 12.55/1225. Daylight on this overcast day: 1790.
Of course what was being measured was not "illumination" but rather "luminosity". I covered the distinction (search "luminous") in an earlier post. I applaud EasyTron for their candor on this point in their web site and in their print materials.
This is an emerging product that could be much more efficiently (and economically) produced off-shore in the lands of rice bowl labor; it is only a matter of time until this innovative product is cloned without royalty payments at a killingly low price. It seems that we export technology and import goods; pretty soon we will be importing both and will live by selling lottery tickets to eachother. As usual, I have informed the principals of EasyTron of this review so that they may correct any of my errors; however I need to be convinced.