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A very wide variety of cabin lighting is available. The proper selection can make a big improvement in the livability of your boat. We hope this guide will help you select the lighting best suited to your needs, whether it be Alpenglow lights or another brand or style.
Cabin lights can be divided into two basic types; area lighting and spot lighting. Round dome lights and most fluorescent lights are examples of area lighting. High intensity lights, reading lights, and swivel lights are examples of spot lighting. Gimbaled lamps and some low-power fluorescent lights fall in between. Spot lighting is a good choice when only one person needs light for a task at a specific location such as reading or working at the chart table. If you need very intense light for detailed work such as instrument repair, spot lighting can be effective if the light can be placed close to the work. A spot light is also good if one person is reading while another is sleeping in the same cabin. If light is needed at more than one spot at a time, area lighting is usually more effective than using several spot lights. One problem with spot lights is that contrast between the illuminated area and the dark background can cause eyestrain.
Area lighting is accomplished with one or more lights (depending on cabin size and lamp brightness) mounted overhead, or occasionally on a bulkhead. By illuminating the entire cabin, shadows are greatly reduced because the light bouncing off hull sides and bulkheads results in scattered light coming from many directions. In order to realize this advantage, the light needs to be fairly bright and it must be wide angle. Take a look at the light pattern diagrams. Notice that the Alpenglow lights give about the same light to the sides as down, and that the incandescent dome light gives slightly more light to the sides than down. Fluorescent examples "A" and "C" give wide angle light to one side only, and example "B" and the twin tube do not give enough side light to provide even illumination. Example "C" also isn't bright enough for area lighting, as you would need to have a book within two feet of it for reading. These fluorescents with focused light and lower light output could be used under a cabinet to light a chart table, etc. In this sense it is more like spot lighting. Gimbaled lights in some cases can be a good compromise. The light is brightest nearby, but they also cast light in all directions which provides some light to the background. Because of the high efficiency of fluorescents, you can usually light the entire cabin with the same power as one spot type light by using a high efficiency fluorescent area light.
Spot lighting is usually incandescent A few use halogen bulbs which are about 25% more efficient, but that isn't a very great difference; so for spot lighting, the choice is mainly just personal preference. Area lighting is a bit more confusing because you have a choice of incandescent or fluorescent and they both have advantages and disadvantages. Incandescent lights are inexpensive, have a pleasant warm color, and are fairly compact, but they are very inefficient and give off a lot of heat. Fluorescents can be about four times as efficient, resulting in much less battery drain, and they give off far less heat. These are very great advantages, but there are some disadvantages. Some people object to the cold color of the light (even "warm white" bulbs are stark compared to incandescent), they are more expensive, the fixtures are usually over a foot long and they are often unattractive. We believe that Alpenglow lights have eliminated most of those problems and gained even greater efficiency. Quality does have a price, and Alpenglows may be more expensive; however, reduced engine time for battery charging will pay for it over time.
One of the main reasons for using fluorescent lights is the high efficiency. Fluorescents vary tremendously, however, with some not much better than incandescent. There is much confusion regarding this; and unfortunately, manufacturers only make matters worse. In order to make an informed choice, we need a basic understanding of light ratings. In advertisements, we see statements like; "equal to 50-watt bulb", "400 lumens", "25% more light than 25-watt bulb" etc. More often than not, these statements are inflated by up to 200%! How does that happen? As you may know, a 12 volt bulb rated at 15 watts uses 1.25 amps (volts x amps = watts). Amps and light output of incandescent lights can be predicted just by knowing the wattage of the bulb. This simple relationship doesn't occur with fluorescent lights, however. The light output of the bulb is controlled by the ballast.
The 8-watt tube used in most conventional marine fluorescent lights can be supplied with less than 8 watts, in which case the light output will be correspondingly less. Some companies do this, but still claim the light output of a fully powered tube even though it's much less. A standard 8-watt fluorescent tube produces about 50 lumens per watt (the compact fluorescent tubes used in Alpenglow lights give 65 lumens per watt). No electronic magic can significantly change that. In addition, all ballasts consume some power, generally 15% to 25%. Therefore a light advertised as using .4 amp (4.8 watts) uses at least .8 watt for the ballast, leaving 4 watts for the bulb. So it isn't an 8-watt light at all. It's a 4-watt light and there's no way that it can give more than 200 lumens. This is an actual example, and that particular light is advertised as an 8-watt light with an output of 400 lumens. Tests show that it is about 200 lumens and power used is .52 amp. So it gives 1/2 the light output and uses 30% more power than claimed. This is not an extreme example. There are some better and some worse. One light is claimed to be 25% brighter than a 25 watt bulb. All we can say is get one and try it. You will find that it is about 1/2 as bright.
Now that we've shown that you can't trust advertising claims; why should you trust us, and how can you make an informed choice? The answer to the first question is that all our tests were conducted under identical conditions with the same test equipment. All the lights tested are typical examples. The Alpenglow lights were picked at random from stock, and the conventional fluorescent lights are random samples of those most widely sold by marine dealers. But don't take our word for it. We encourage you to buy only from sources that allow you to try the lights and return them if you aren't satisfied. Get several lights (including Alpenglow, of course) and make your own comparisons. You can easily make actual tests if you like. An expensive lux meter isn't necessary for approximate tests. All you need is an incident reading photographic light meter; however, visual comparisons are generally satisfactory. Fluorescent lights (and particularly Alpenglow lights) need about a minute to warm up to full brightness, so be sure to warm up all fluorescents before making comparisons. Also, be sure to compare brightness to the sides as well as straight below the lights.
The Night-Vision option for our overhead lights now uses state-of-the-art Light Emitting Diodes for the red light. We use Superflux LED’s which are bright enough for reading. Power consumption is an incredibly low 1/15 amp (65 ma) on red. It would take 20 amps to get the same red light from an incandescent bulb! With he dual power option, you also have a low level red for minimum night vision impact.
This change is a result of our commitment to use the best technology and materials to bring you the highest quality, most efficient, most reliable cabin lights available. The white light is provided by the same fluorescent technology that has made Alpenglow the quality leader in marine lights.
White LED’s have been making slow but steady progress, and we believe that they are now suitable for some interior lighting applications. We’ve been testing and building prototypes for over ten years, and they finally have reached the point that they are good enough for limited use in Alpenglow Lights. Unlike colored LED’s, the white LED’s are actually less efficient than our compact fluorescent. The currently available white LEDs produce about 30 to 50 lumens per watt which is more than double that of incandescent bulbs, but compact fluorescent tubes produce 65 lumens per watt. The most efficient of the white LEDs are an extremely cold color that we consider unacceptable for any interior application. There are now some LEDs that are called warm, but they are still a cooler color than what we generally prefer for interior lighting. We still don’t consider either the efficiency or color to be adequate for general area lighting, but for supplemental applications like reading lights, they can have some significant advantages. We now have an LED version of our reading light, which you can read more about on the Reading Light page of this web site. For general area lighting, LEDs still don’t come close to our compact fluorescent overhead light. You can be confident that we will continue to use the best technology available and will be monitoring future white LED development.
What About Cold Cathode Lamps?
We have been getting a number of questions lately about cold cathode lamps. In keeping of our philosophy of using the best technology available, we investigated cold cathode technology several years ago and rejected it for several reasons. The manufacturers we talked with didn’t recommend their use for area lighting. They are designed for illuminating instruments and LCD displays; applications requiring small amounts of light in precise locations. The only way to get enough light for area lighting is to use a lens that focuses most of the light straight down. While this does provide adequate light over a small spot, it is at the expense of wide angle illumination. Although cold cathode tubes have a long life, when they do burn out, they are not user replaceable. The entire fixture must be replaced unless it can be returned to the manufacturer for tube replacement. As always, our advice is to make side by side comparisons. A 9-watt Alpenglow light on low uses about the same power as a 5-watt cold cathode light. Compare the brightness not only directly beneath the fixtures, but at various angles off to the side. There are good reasons why every manufacturer of high efficiency lighting for residential use uses compact fluorescent technology.
Copyright 2002 by Alpenglow Lights