Let There Be Light: How to Choose Dive Lights

Light Type

There are several different types of dive lights you can choose from: primary lights, secondary (back-up) lights and photo/video lights.

Primary dive lights are usually the largest and the brightest of all. Although they can be quite heavy, powerful primary torches will allow you to light very dark areas when needed. They should also have a long-lasting battery and be very durable.
Secondary dive lights are generally more compact and lightweight. Their main purpose is to serve as a backup in case the primary light fails. It is great if your secondary light is small enough to fit in your pocket so that you can only take it out when needed.
Photo/video dive lights are specifically designed to adequately light your subjects. Usually, photo lights come in the form of an external flash, also called a strobe. Strobes work by discharging light at various power settings. Each power setting normally relates to a flash duration. Video lights need to have a wider beam angle and high lumen power in order to illuminate the scene evenly. The majority of modern video lights use LED technology. If you want to get a single torch that will serve as your focus and video light, it’s best to buy a powerful light with several beam settings.

Remember, it is best to carry two dive lights at all times, especially during your night dives. Even if your primary light seems to be working fine at the start of the dive, you can never really predict what could happen.

Dive Conditions

One of the most important factors to consider when choosing a dive light is how you plan to use it.

If you are looking for a good primary light for nighttime, your best bet would be a bright dive light with a wider beam angle. Pay attention to the grip of the torch. Many divers find it more comfortable when a bigger and heavier light comes with a pistol or lantern grip. Don’t forget, however, to take the water conditions into account as well. The murkier the water, the more powerful your light should be. On the other hand, if you are diving in clear water at night, it is best to bring a smaller light. One reason for this is the wildlife within the water. Many of the creatures are used to the dark and will scurry off or become stressed when a very bright light is shined in their direction. By using a smaller light, you are respecting the animals in their habitat and are less likely to disturb them.

If you need a light to use during the daytime to explore the little caverns and crevices or look under the rocks, a small lightweight stick light with a narrow beam would be a good option.

If you want to expand the capabilities of your GoPro and bring back the color lost in the water column, you need to find a good compromise between size and power. If you plan to mostly shoot video with your GoPro, all you need is a continuous source of light that can be positioned on a tray with handles or even attached to the existing GoPro mount. For still images, especially wide-angle photography, you would generally need slightly more power, or even the second light to fill in the shadows.

Those, more serious about underwater photography, will need a light (better two) with a wide, consistent beam and no hot-spots, plus some strobes and/or a rig to put the system together. Another point to remember is that when you are shooting a wide-angle image, the light should be even across the field, maintaining good intensity further away from the center of the beam.

Finally, a torch for technical diving should have a bright and tight beam and a very long battery life.

Lighting Technology

Divers have several options when it comes to light head/bulb types: Xenon (incandescent), LED (light-emitting diode), and HID (high-intensity discharge).

Xenon dive lights tend to be the least expensive of the three options. Another advantage of this type of torches is that they emit a warm natural light, instead of the bluish beam of the LED or HID torch. On the downside, however, Xenon lights don’t provide as much brightness as the other two options and have shorter battery life.
HID dive lights utilize electronics to increase the output of their bulbs, and are, therefore, extremely powerful. These lights have a nearly white beam with the hints of blue or green, depending on the model. Keep in mind though, HIDs are very delicate (so no rough handling) and quite expensive. Due to this HID torches are used almost exclusively as primary lights for technical diving and underwater photography.
LED dive lights are very durable, efficient and powerful. What’s more, due to the constant improvements in technology and manufacturing of this type of lights, LED torches have now become pretty affordable and popular among all types of divers.

Batteries

The battery that powers your torch is another consideration. You can choose between rechargeable or non-rechargeable versions.

Dive torches with rechargeable batteries are best for avid divers who are frequently in the water. They will save you money by eliminating the necessity to buy new batteries every time you go diving. Rechargeable batteries are also the most environmentally friendly, since they can be reused. That said, you will need access to power and time to leave them to charge.

Dive torches with non-rechargeable batteries typically come shipped with standard alkaline batteries. The upside is that these are relatively inexpensive and replacements can be found pretty much everywhere in the world. However, they have a lower level of performance and reduced battery life. If you want a bit more performance, you can upgrade to lithium batteries. They are slightly more expensive and might not be available in remote locations.

Maintaining Dive Lights

Now, after you choose a suitable dive light, you need to remember a few simple maintenance rules that will help you prolong the life of your light.

Before you dive, reassemble your light and check that every part of it is debris-free.
Insert a set of new batteries or charge your rechargeable ones.
Test the light by turning it on and off to make sure that it is in good working order.
After you dive, be sure to rinse your torch in fresh water along with the rest of your equipment.
After your torch has dried, lubricate it if needed. Store your light in a cool, dry place out of direct sunlight. Protect it from being damaged or dropped.
If you won’t be using the light for an extended time, store batteries separately.
Last but not least, always follow the manufacturer’s instructions for maintaining your dive light. Follow all recommendations and use only approved substances for lubricating o-rings.