Features September 2001 Issue

Brinkmann, LSI, Optronics Shine Bright in Spotlight Test

Plug-ins and rechargeables shoot the best beams; drycell-powered lights last longer, but don't have the punch to penetrate the gloom.

If you've ever tried to locate a channel marker on a dark night, or to read the number on an unlit buoy in the rain, you already know the value of a handheld spotlight. While other types of lights such as fixed-mount spotlights or flashlights have their uses, they also have their limitations. In terms of flexibility and convenience of use, there's nothing like the bright, narrowly focused beam of a good handheld unit. 

Lights were shined on a green navigational
buoy from about 900 feet away. We noted the
strength of illumination, and just how much
scatter each light generated.

In recent years, the manufacturers of these spotlights have been indulging in the optical equivalent of the old automotive horsepower race. Who can claim the highest candlepower number? Well, brightness is indeed important, but it's certainly not the only consideration in selecting a spotlight. For this report, we obtained no fewer than 16 different spotlights and ran them through their paces.

How Spotlights Work
There really isn’t a great deal of complexity to a handheld spotlight, which means that each part is essential to good performance. Every one has an incandescent bulb, a reflector, and a switch encased in some sort of housing with a lens. Every one operates from a battery, whether it's the boat's house battery, a rechargeable battery inside the housing, or dry cells (or a lantern battery.) Most have hand-grips, although a couple are clearly intended for clamping to a rail.

The reflector used in all the lights we tested is parabolic in shape. A parabola has the unique property of reflecting all the light striking its surface from a point source in the same direction. A perfect parabolic reflector six inches in diameter would reflect light from a single source at its focal point in a beam 6" wide. Thatbeam would illuminate a circle six inches wide at any distance. Reflectors, though, aren't perfect. More significantly, light bulb filaments are not point sources of light, so some portion of the light is reflected outside of our theoretical 6" circle, resulting in a spread of light that has been described as scatter, spatter or glare.

For marine use, the less scatter the better. Any light is going to be reflected by fog, but a really tight beam minimizes this effect. There's been a theory that beam spread is a good thing because it helps estimate distance. While this may be true to some extent, the beam angle of any real-world spotlight is large enough to make distance estimation possible. More glare than is unavoidable is not a good thing.

In theory, again, one would expect that a perfect light bulb/parabolic reflector combination would produce a perfectly round beam. Not so in real life, for the same reasons. A concentrated circular spot of light would be desirable in that it would put all the light energy in the smallest possible area, giving maximum brightness. It would also minimize back-reflection from fog and spray. Almost as good, in our opinion, is an elongated light spot, providing the elongation is horizontal. Such an arrangement makes it a bit easier to find the object you're searching for without too great a loss of intensity.

As with any portable light, there's a trade-off between how bright the light is and how long its batteries will last. One popular way to minimize drain is to plug the spotlight into an accessory socket—the cigarette lighter socket—and run it directly from your boat's house battery. This is a fine approach but requires a cord long enough to reach the power source. Plug-in models are very light, which can be a real plus, depending on who's holding the light and how long it has to be held. At the opposite end of the power spectrum are handheld units that use dry cells. These require no connection to the boat but are heavy and not very bright.

In the middle are those models that use a built-in storage battery that can be recharged from the boat's house battery. Some of these can also be recharged from an AC source, using an adapter. These are extremely convenient and can be extremely bright. Their major drawbacks are that they're relatively heavy and have a relatively short operation time before requiring recharging.

Switches are a potential weak spots on any onboard electrical device. Unless special attention is paid to making it water-resistant, a switch represents a failure waiting to happen. Cases, too, present a threat. We prefer tight-fitting cases with as few joints as possible, and with O-rings to keep water out. Fastenings and metal fittings should be stainless, of course.

How We Tested
We tested each of the 16 models for brightness, beam pattern and spread, and (subjectively) for how well they seemed to light things up. We weighed each one, noted handling ease, ease of operation, and balance. We examined fit and finish of cases and quality of fittings. We noted features, power cord length, and type.

The major claim made for most of these spotlights is candlepower. The ones we tested had claims ranging from 2,200 to 3 million. We did our brightness tests, not on the output of the spotlight, but in terms of the light reaching the target. This is measured in foot-candles and takes into account the fact that a light gets effectively dimmer the farther away it is.

The relationship between candlepower and foot-candles is a simple one: a 1-candlepower light 1 foot from the target will provide 1 foot-candle of illumination. Double the candlepower and you'll double the number of foot-candles at the target. Double the distance, and you'll cut the foot-candles by a factor of four—illumination varies with the square of the distance. We measured foot-candles with a meter that measures the illumination of light striking it. We placed each lamp exactly 30 feet from a sheer stone wall, aimed the light at a mark on the wall and measured the illumination at the mark. This testing was done in virtually total darkness. There were no street lamps or traffic, and no moon.

There's always a question of what voltage to apply when testing a plug-in. With an engine running, the alternator develops about 13.8 volts. With the engine off, this can drop as low as 11.8 volts. We think that people who depend on handheld spotlights are apt to use them under difficult conditions—conditions under which the power is on. For the plug-in models, we took power from a large battery being charged by a car's alternator.

This test also allowed us to see what kind of light pattern or beam shape each produced and make judgments about handling, balance and convenience features.

Finally, we took all 16 products out for a night on the water to see how well actual experience matched our measurements of performance. We anchored 0.15 nautical miles (about 900 feet) from a navigational buoy on a dark night and tried to use each spotlight to locate the buoy.

What We Found
We found enough differences among the lights, and enough similarities among lights of a particular type, to convince us that we should discuss them by groups: drycell-powered, plug-ins, and rechargeables.

Drycell-Powered Spotlights
We had five lights that obtained power from removable and replaceable drycells. Two of these, the Pelican BriteLite #5000 and the Pelican LaserPro 4D, require four alkaline D-Cells. The other Pelican product, the King Pelican Light, uses eight D-cells. ACR's Super Beam Gun uses a less commonly available 6-volt lantern battery. All four of these products, as far as construction is concerned, are superb examples of how to build seagoing equipment. Each of the four has a heavy, one-piece molded case, a shock-resistant mounting of internal components, and a waterproof switch. (The ACR uses a magnetic switch, while the Pelican products rely on rubber seals.) To get at batteries and to replace bulbs, you remove the faceplate/lens. The three Pelican products have screw-off faceplates with O-ring seals; the ACR uses a press-on/pry-off rubber ring that holds the lens and relies on a large hose clamp to seal it against the spotlight's case. Both systems work, but we found that prying off the ACR's rubber lens housing was a real nuisance: Instructions specifically warn against prying with a screwdriver or such like, and the rubber wasn’t that flexible. Result? Installing a battery took considerably longer than it should, and our testers had some sore fingers.

The Pelican products shared a very nice feature: They use twin-filament bulbs, with only one operating at a time. This can be a boat-saver if a filament burns out in a tight situation. The King Pelican light features a versatile handle assembly that can be attached to the light in a variety of configurations, somewhat mitigating the weight penalty of its extra four D-cells. The other four have pistol-type grips; the Pelican LaserPro also has an adjustable stand, a handy feature if you want to use it as a work light.

The fifth self-powered light was the Brinkmann MiniQBeam—a plug-in light that offers the option of dry-cell operation. It's small, light, and by far the least expensive of the five, but it just doesn't have the ultra-rugged construction of the others. We think that it's better judged as a plug-in model.

All of the self-powered spotlights have the obvious advantage of not having to rely on power cords, an arrangement that lets you move around the boat with a maximum of freedom. They're not very bright, largely a limitation imposed by using dry cells. Four D-cells provide you with six-volt power and a limited capacity for energy storage. Even the eight D-cells used in the King Pelican light, while they provide 12 volts, are limited in the amount of electricity they can store compared to the capacity of a boat's house battery. We think that they're best suited for use on a small boat or tender that doesn't have a house battery, or as a sort of super flashlight to supplement a more powerful plug-in or rechargeable spotlight. The King Pelican Light and BriteLite as well as the ACR Super Beam Gun can double as dive lights; the BriteLite even provides auxiliary weights to give it neutral buoyancy for diving applications.

Plug-ins
Eight of the spotlights we tested were powered by the boat's house battery. They have a long power cord that plugs into a cigarette lighter socket. This can be a severe disadvantage on a large boat, or in situations where you must frequently leave the helm. For most boaters, we've observed, this isn't the case, and the required power cord becomes more of a nuisance than a problem. The fact that a boat's house battery is a more potent source of electrical power than a dry cell—both in terms of higher voltage and greater capacity—shows up in the brightness of the plug-ins compared to the drycell-powered models. The brightest of the cell-powered spotlights provided an illumination of 9.5 foot-candles, while the plug-ins gave us readings ranging from 27 to 146 foot-candles. We tested the plug-ins at 13.8 volts—what you'd get with the engine on and the charging circuit operative.

The plug-in models are very light, ranging from 14 ounces to just under 2.75 lbs. Our drycell-powered lights weighed from just over 2 lbs. to almost 5 lbs.

Brightness is important, but it's far from the only consideration. The most noticeable finding was the obvious one that some lights are brighter than others, and some have a smaller, less-scattered beam. We also found that unless differences in brightness are large, they're not particularly meaningful. Our ability to discern the target marks was just about the same for a light rated at 400,000 candlepower as it was for one with a 2,000,000-candlepower rating. Due to nonuniformities in any given light pattern, the actual brightness can vary considerably, depending on exactly where in the target you take your measurements. We found that illumination could vary by a factor of 2 to 2.5 foot-candles without making much difference.

A tight beam with little scatter is an important consideration. It reduces glare from fog and makes it easier to find a target. Tightness of the beam pattern, while a difficult parameter to quantify, was one of the factors we considered in our testing. Some designs, such as Optronics Blue Eye Beam, have tinted areas on the lens to help control the beam.

There are a number other factors not directly related to optical performance but nevertheless important. We've found that the only power cords we're willing to live with are coil cords. We've tripped over enough uncoiled cords to be thoroughly disgusted with them. Of the two basic switch designs we encountered with the plug-in spotlights—the open, non-waterproof trigger or the rear pushbutton with a waterproof rubber boot—we strongly prefer the latter.

The sealed beam design of some of the units tested is ideal. Sealed beam models have the added advantage of never going out of focus. We prefer longer cords for any device that must remain plugged in when in use.

Our favorite among the plug-in models was the Optronics Blue Eye Beam. It wasn’t the brightest—the Optronics Night Blaster won in that category—but it was adequately bright, had a commendably tight beam, a waterproof switch, and a 10-foot coil cord. It weighed in at an easy-to-handle 1.75 pounds. Our sea test confirmed this opinion. Our testers found it to be the easiest of plug-ins to use.

Oddly enough, the Optronics Blue Eye Beam is rated at 400,000 candlepower; our next choice is the similarly designed Optronics Night Blaster 101. This Night Blaster is rated at 1,200,000 candlepower, but provided slightly lower foot-candle readings at our test target and proved less effective in our on-the-water test.

If you feel that you need a floodlight in addition to a spotlight, the Brinkmann 800/1302-0 has a two-way switch (not waterproof) to select between flood and spot. And if you’re looking for a spotlight to clamp to a rail rather than a handheld, there’s the Night Tracker Sport UtilityLight. (No, it doesn't have four-wheel drive.) In fact, that's about the only way you can use it, since it doesn't have a handle.

Rechargeable Spotlights
Rechargeable spotlights, in most respects, represent the best of all spotlight worlds. They can be charged either from 110-volt AC ashore, or through an inverter; they're among the brightest spotlights made; they don't require battery changes as do the drycell-powered models, and they can be unplugged and used without the restriction of a power cord.

On the downside, they're heavier than the plug-ins—typically 3-4 lbs. And the ones we tested, at least, lack some durability features, such as the tight-fitting cases and waterproof switches that appear on the better plug-in models.

None was equipped with a cord coil, possibly because manufacturers feel that they're not going to be used except in the cordles mode. That's a shame, because the ones we tested will operate when plugged in, without concern for the state of charge. None can be operated directly from AC power, though that's not much of a limitation, in our view.

We found the performance of this entire group to be very good, with the standard Brinkmann Q-Beam 800-1700-2 leading the way, largely due to a very tight beam pattern. Both in our lab and sea tests, this was our testers' top pick. Once again, we found that rated candlepower is a snare and a delusion. The Brinkmann, rated at 500,000 candlepower, performed just as well, if not better, than the Night Tracker #3800 (2,000,000 candlepower) the Nite Guard (1,500,000 candlepower), and the Optronics Night Blaster (1,500,000 candlepower).

Conclusions
Our conclusions are presented in tabular form on pages 34-35. We divided the spotlights into three groups: drycell-powered, plug-in, and rechargeable. (One model, the Brinkmann Mini Q-Beam, is listed twice, since it can function as a cell-powered light as well as a plug-in.) Within groups, the lights are listed in decreasing order of preference from top to bottom, based on our test results and our judgments of quality and performance.

A rechargeable spotlight is the best choice, we think, even while recognizing that none of the four we tested can be considered as seaworthy as some of the plug-ins or cell-powered models. If you have a boat where you'll never have to use a spotlight from more than a few feet away from the helm, one of the better plug-ins should suit the bill fine, even if you're not compulsive about protecting oyur equipment.

While we like several of the standard cell-powered models as flashlights/lanterns, we don't think that any of the ones we tested provide an adequate replacement for a good handheld spotlight.

Also With This Article
Click here to view "Value Guide: Handheld Spotlights."

 

Contacts- ACR Electronics, 5757 Ravenswood Rd., Fort Lauderdale, FL 33312; 954/981-3333, www.acrelectronics.com/. Brinkmann Corp., 4215 McEwen Rd., Dallas, TX 75244; 800/527-0717, www.thebrinkmanncorp.com/. Guest Co., Inc., 95 Research Pkwy., Meriden, CT 06450 203/235-4421, www.guestco.com/. Lectro Science, Inc., 919 Sherwood Drive. Lake Bluff, IL 60044 800/453-2101. Optronics, Inc., 350 North Wheeler St., Fort Gibson, OK 74434; 918/683-9514, www.alcatel.com/telecom/optronics/. Pelican Products, 23215 Early Ave., Torrance, CA 90505; 310/326-4700, www.pelican.com.

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