Practical Sailor Sheds Some Light on LED Flashlights

In a search for the perfect, energy-efficient flashlight, testers evaluate brightness, beam quality, and utility.

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Testers evaluated 25 different flashlights. Among these were products from Inova, Underwater Kinetics, Tektite, Sea Fit, Streamlight, Garrity, Pelican, Dr. LED, and IQ Lights. The goal of this test was to find a flashlight that was compact, light, and provided superior spotlight and wide angle illumination for objects in close range. Unfortunately, no light we tested answered all of these requirements. The winners proved to be units that excelled at one. We also discovered that size still matters, and more batteries means more power, more light, and more life. The best marine flashlight is one that suits your needs. A well-equipped sailor needs a few different flashlights to cover all the bases: one thats a dedicated spotlight, one that lights up the lockers, one that serves the needs of bright, wide angle floodlight, and lastly a tiny pocket light used for in-the-cockpit chart reading or other instances when you need a quick light but want to preserve your night vision.

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Underwater Flashlights

Ralph Naranjo

A technological evolution has made flashlights smaller, lighter in weight and brighter, allowing them to be easily carried in a pocket or attached to an inflatable PFD. They range in mission from micro-size devices that give momentary illumination to insert a key or check a chart, to compact, waterproof spotlights that will illuminate a mark a quarter-mile away and keep on working no matter how wet they get. With the rapid growth of light emitting diode (LED) technology, the range of alternatives has become even greater.

What We Tested

For this test, Practical Sailor focused primarily on smaller LED flashlights, although some Xenon and conventional incandescent bulbs were included for comparison. Eight manufacturers submitted products for review. Some, like Pelican, are familiar brands from past tests. Others, like Dr. LED are relative newcomers riding the technology wave. Ultimately, testers found that although the new generation of LED flashlights are bright and low in power demand, when it comes to spotting buoys at a distance and focusing a tight, bright beam, Xenon bulbs-like those found in the tested mini dive lights from Underwater Kinetics-couldnt be beat. 

How We Tested

In our comparison, testers looked at spot versus flood lighting, beam focus, brightness, the color of the light, and how power consumption affected battery life. Baseline evaluations included light meter bench tests (see “How We Tested”), reflected light luminosity readings (measured in lumens), a navigation-mark illumination evaluation, and a series of tests that simulated onboard light usage. Testers also inspected the construction quality and measured the battery life of each light. Products that carried a water-resistant rating were splash-tested and units deemed waterproof were immersed. We evaluated each lights ease of operation and scrutinized disassembly and battery replacement.

Color Temperature

Photographers refer to color temperature as the hue conveyed by a beam of light. Mid-day sunlight is around 5500 degrees Kelvin while more amber afternoon sunlight is approximately 3500 degrees. An incandescent light bulb measures in at about 3500 degrees, consequently white paper looks a little more yellow under a typical lamplight. These examples of color temperature relate to what a “black body” object would look like at a specific extreme temperature. Because LED lights are cool, and have no heated, glowing filaments, they are rated according to the color that they produce. LED chips emit blue light and bits of phosphor are added to reradiate a more natural color. Recent advances in LED technology are allowing these lights to produce more lumens per watt, with better beam focus and a more eye-appealing color, so it will be interesting to see what the future holds for LED flashlights.

Batteries

As expected, the LEDs in this test produced a usable amount of light for a much longer period than other types tested. Battery type varied among the units. Size AA was the most popular, although there was a notable number of size CR123A 3-volt lithium cells. Testers measured no-load voltage at the start and finish of each test. On average, when LED devices and Xenon bulb lights of similar initial brightness were compared, the LED units length of useful light was often three to four times that of the power-hungry Xenon light. Alkaline batteries provided the longest life, but rechargeable batteries make sense for a sailor who uses his flashlight frequently.

Underwater Flashlights

Powerful Spotlights

One of the most valuable functions of a flashlight is its spotlight function or ability to tightly focus a light beam and illuminate a distant target. Our principal field test of this function was the illumination of a fixed navigation mark approximately 200 yards away.

Underwater Kinetics SL4 Sunlight was the hands-down winner of this test. The Xenon bulb/reflector combination sent out a piercing beam of warm light that cut through haze and allowed the navigation aid to stand out brightly. Its interesting to note that Underwater Kinetics SL4 eLED version of the same power pack was not as effective in this test. Designed primarily as small dive lights, both of these units should appeal to sailors.

Also showing strong performances in this category were Pelicans Recoil 2410 Submersible Stealthlite, an LED light with a proprietary element in the reflector path that does a superior job of eliminating glare. It produces almost no flood effect at all and keeps its beam collimated (parallel) over its entire range. The Pelican light is uniformly bright and even, showing no sign of concentric rings or distortion. Underwater Kinetics smaller AA cell-powered Xenon Mini Q 40 was also a bright spot illuminator, although its beam was irregular in shape. Other bright, compact, lightweight (123A cell) performers included Inovas well-made XO3 and Dr. LEDs finely machined compact MI6 flashlight.

Locker Lookers

Effective close-range illumination requires less light and a wide-angle beam for a flood effect. High-power spotlights reflect off shiny, gelcoated surfaces, impairing night vision, and can be harmful to retinas exposed by dilated pupils. Inovas very handy 24/7 has a rotary switch that lets you select either a red or low-intensity, white light. Further rotation in the white light direction increases brightness. The lights additional selections include emergency flashing light combinations, one of which is a handy, automated repeating S-O-S signal. The low intensity light on the new MI-6 from Dr. LED makes for a good locker looker, but unfortunately for sailors, the first click of the switch selects the spotlight. Bouncing this light off a white cockpit bulkhead is like firing a flash.

The multi-diode Streamlight proved to be an easy-to-handle utility light with a convenient pushbutton switch. It provides a bluish, but useful, floodlight for close-up work. Flashlights with a bright, narrow central beam and uneven secondary halos cause too much reflected glare on reflective surfaces and the lighting is too uneven for illuminating onboard targets (See “Shedding Light on Flashlights”).

Housing and Switches

Simple switches tend to be the most reliable, and it can’t get much simpler than one O-ring-sealed screw cap that both opens the battery port and also functions as the on/off switch. Most of the aluminum and plastic flashlights we tested used this type of switch, while the Inova units also incorporated an push-button in the end cap that allowed intermittent light or signaling. Dr. LED, Streamlight, Sea Fit LED and Underwater Kinetics LED zoom all incorporated push-to-click switches into their housings. One switch, the UK zoom light switch, malfunctioned during testing, although UKs other light switches-including the twist-on switches on the MiniQ lights-functioned flawlessly. The toggle switches built into the waterproof Pelican Light and UKs SL4 models served well during initial testing.

Underwater Flashlights

Dive Lights

Underwater Technologies, Tektite, and Pelican target divers, but their lights are as useful above the water as they are below. These lights tend to offer bright beams, rugged housings, and are as at home on a sailboat as they are in a divers gloved hand.

Though its brightness was less than inspiring, Tektites Trek 400 did offer one unique characteristic that could prove to be a real winner in a search-and-rescue situation: The light floats with the beam vertical, where it might be visible in a search-and-rescue operation.

Findings

At the onset of our testing, we were looking for a flashlight that was compact, light, and provided superior spotlight and wide angle illumination for objects in close range. Unfortunately, no light we tested answered all of these requirements. The winners proved to be units that excelled at one task and werent designed to cover all bases. We also discovered that size still matters, and more batteries means more power, more light, and more life.

When it comes to the brightest light in the pack, the honors went to Underwater Kinetics SL-4 Sun Light with a power-hungry Xenon bulb that provides four hours of usable light per set of four alkaline C-cells. This rugged ABS molded dive light does double duty as a handy mini spotlight thats great for checking marks and whats going on at the masthead. Although the light is not an LED, its superior spotlight, waterproofness and price deserve earned testers recommendation.

Not far behind in the spotlight category was the Pelicans Recoil Stealthlite 2410, the testers favorite light overall. This lightweight, ergonomic four AA-cell LED is submersible and comes with a unique focusing technology that nicely collimates the beam. It also has a useful light span of over 24 hours, and a glow-in-the-dark lens lip that makes it easy to find in the dark.

Tied in the mini metal light category were Inovas powerful XO3 and Dr. LEDs MI-6, both bright, well-crafted lights. Both projected a bright spot beam but also produced a slight flood halo that decreased spotlight performance in moist marine conditions.

Our close-up, wide-angle needs were best served by Tektites Expedition Star, a triple C-cell dive light with an ABS housing. This powerful, and long-lived LED light source can brighten up a locker or light up the darkest recesses of an engine room.

When it came to close-up work and chart reading, our testers favored the compact, lower-power Inova multi-diode X5. The flashlight produced a very even clean disk of slightly blue light. Inova also scored another hit with its clip-on 24/7 convertible headlamp flashlight that allows a user to scroll through a range of useful white and colored options. If youve only got $10 to spend for this duty, the IQ Lights SP-3 is handy.

Conclusion

LED designs are taking over the industry thanks to their cool use of energy and resulting efficiency. However, focusing and color correction are still an issue. When it came to cutting through hazy marine air, a Xenon bulb, not an LED, was the right answer. Of the LED lights we tested, only Pelican provided a spot beam free from the effects of peripheral glare. Worth noting however, is that after about an hours worth of use, a comparable LED light could match the best Xenon bulb in performance.

A well-equipped sailor needs a few different flashlights to cover all the bases: one thats a dedicated spotlight, one that lights up the lockers, one that serves the needs of bright, wide angle floodlight, and lastly, a tiny pocket light used for in-the-cockpit chart reading or other instances when you need a quick light but want to preserve your night vision. Our winners circle is a good round-up of the diverse capabilities we saw. These lights, and most of the others in the evaluation, show just how far the technology has come. Gone are the days when a good flashlight had to be the size of a shillelagh and the weight of lead pipe.

Darrell Nicholson
Practical Sailor has been independently testing and reporting on sailboats and sailing gear for more than 50 years. Supported entirely by subscribers, Practical Sailor accepts no advertising. Its independent tests are carried out by experienced sailors and marine industry professionals dedicated to providing objective evaluation and reporting about boats, gear, and the skills required to cross oceans. Practical Sailor is edited by Darrell Nicholson, a long-time liveaboard sailor and trans-Pacific cruiser who has been director of Belvoir Media Group's marine division since 2005. He holds a U.S. Coast Guard 100-ton Master license, has logged tens of thousands of miles in three oceans, and has skippered everything from pilot boats to day charter cats. His weekly blog Inside Practical Sailor offers an inside look at current research and gear tests at Practical Sailor, while his award-winning column,"Rhumb Lines," tracks boating trends and reflects upon the sailing life. He sails a Sparkman & Stephens-designed Yankee 30 out of St. Petersburg, Florida. You can reach him by email at practicalsailor@belvoir.com.

13 COMMENTS

  1. I thing to keep in mind when using LED lights is the RF noise they generate. Led’s are current devices, and there is always a circuit that controls the amount of current to the led. These are often simple pulse width modulators. If they are not shielded property they could produce enough RF noise to interfere with radio usage.
    I believe that there is now a new standard for this when used in a marine application. However, diving usage may not require this standard.

    • if you look inside the Pelican e.g. you will notice there is not a single electronic component – thus no RF noise at all…………….
      Have NEVER experienced RF interference with any LED lights on boats – Even the ones (Like the Lopolight nav lights) that actually have electronics in them.
      I am sure some cheap junk Chinese switch mode controllers could drown out a VHF and/or AIS though.

  2. I like LED flashlights for their small size, bright light, and long battery life. One downside that I don’t see discussed is the fact that they don’t give you any warning when the battery is getting low, the output just goes from working fine to dead. Old fashion flashlights with tungsten bulbs and carbon-zinc batteries would gradually get dimmer, providing plenty of warning that its time to change the battery. You could shake a dead light or bang it on the bulkhead and get a very dim light that was enough to perform a crucial task like opening a combination lock after returning from shore. Since switching to LED flashlights I started carrying spare AA batteries in my shore bag and in a pocket of my foul weather gear.
    Recently, several lights have appeared on the market that have low battery indicators built in (like the Dorcy 250-Lumen Weatherproof Tactical LED Flashlight with Battery Indicator Light, Black (41-4297) or the Coast XP11R). I have postponed upgrading my flashlights until I find a suitable replacement with this feature, as I expect that this feature will “trickle down” to the less expensive lights.
    The other important feature is battery type. My GPS, VHF and all my flashlights use AA cells. The AA is only a little more expensive than a AAA but has more than twice the power. I would rather have a larger flashlight with longer life and stick with a standardized battery type.

  3. This is a reprint of a 2007 story. Hard to believe it is still relevant 14 years later. Like many old sailors, I have dozens of expired flares and am weary of buying more. In searching in past issues, I cannot find any comparison of electronic LED replacements for flares which sellers advertise as USCG approved. How about a comparison?

  4. Over the years, batteries have gotten much better, bulbs have gotten hugely better, and casings and lenses are better; all great news. But the bugaboo is the switch. They are still awful, and anyone who has owned a few of them while living on a boat will know that you always need 3 of them in every use location because 2 of them won’t work when you need them. Those damnable little switches seem like the simplest part but are the first things to fail after a few months. One must keep replacing them because the salt and water and humidity and general fungus of the universe get into the switches and kill the whole device.

    Your test procedure did not delve into MTBF longevity issues, so your results are fine as far as they go. But the lifetime of the switches is critical to the whole product, and thus critical to the cost:benefit ratio. No one should purchase flashlights without being aware of this failure point.

  5. I am an avid diver and instructor. I have had good experiences with UK underwater lights. And I do a lot of night diving, often in excess of a hundred feet. I still have a few that work fine after 30 years of use. I just keep the o rings lubed occasionally with silicon grease.

  6. We recently recirculated this report in our free newsletter “Waypoints” as a companion piece to promote our upcoming report on Electronic “Flares” (Electronic Distress Signaling Devices) which will appear in the June 2021 issue. This report is dated, and LED technology is constantly evolving and improving. However, of the significant features — seals, switches, and form factors– have remained unchanged since this report. Similarly, the leading manufacturers featured in this report remain leaders in the field, something to consider as you search among the newer models. If you have experience with some of the newer generation lights we’d love to hear about it! Look for our upcoming report on Electronic Flare in the June issue. We also looked at MOB lights in various reports — most recently in the February 2016 issue. 

  7. I have been using the Streamlight Waypoint LiOn rechargeable pistol grip search light for a few years. I think it is awesome, the best I have used. Its beam is tight and piercing. It is the first searchlight I can use from the cockpit without the foreground being to bright.

  8. I read through the entire piece, thought it was incredibly helpful and believed I was now equipped to update my flashlight collection. Then I got to the comments were it was pointed out that the article was originally published 14 years ago. Seriously? This is rapidly changing technology and quite frankly I suspect that most if not all of the information in this article is not only obsolete but misleading. Shame on you “Practical Sailor”. You are better than this.

  9. Thanks for the feedback, he products have changed some, but many of the observations are still valid — and many of the leading brands are still leading brands. The article was recirculated recently to generate input on products that should be included in our forthcoming LED flashlight test, as well as a companion piece to the report on LED distress signals in the June 2021 issue that is available only to paid subscribers to the magazine. We appreciate the time taking to respond. If there’s something you’d like to see tested let me know here: https://www.practical-sailor.com/contact-editor