A commonly-held belief during prior generations and monarchies, is have an heir and a spare. The sentiment is also true with many pieces of scuba gear, including lights.
The deeper you descend while diving, the more the water filters out the sun's light. Eventually, the sun's beams can no longer permeate the water, leaving you in the dark - unless you're a prepared diver. You may also need a light to peek into crevasses along a wall that is teaming with countless samples of sea life or to read your every-important non-illuminated compass, air gauge, or depth gauge.
Dive lights can also be used as a signaling device between buddies. Perhaps you just found an amazing starfish and your dive buddy is looking at some kelp. You can use your dive light to catch your buddy's attention so he/she doesn't miss out on your underwater find.
If a little fin is good, a lot must be better! As true as that statement sounds, it is actually quite incorrect. Fins are a sport-specific piece of equipment that can greatly affect how well you perform during your time in the water.
If you are looking for a primary dive light, a broad beam is probably what you're looking for. Wide beams cover more area, allowing you to maintain a wider field of lighted vision. Your primary light will allow you to view the sea life that surrounds you, as well as your non-illuminated gauges and compass (if applicable).
If you are looking for a backup light, selecting a light with a narrow beam might be ideal for you. This al- lows you to use your light to illuminate cracks and crevices in walls, wrecks, reefs, and rock formations. Backup lights tend to be smaller than primary lights, allowing them to stay out of the diver's way until they're needed.
Before deciding which dive light to purchase, take your diving habits into consideration. Are you a deep diver (more than 100 feet) or do you stay in the recreational diving range (0-99 feet)?
If you choose a dive light that is not depth rated for your desired dive depth, you may find yourself in a very bad situation. Lights that are taken to depths that are greater than their approved rating face leaks, break- age, and other malfunctions.
There are a wide variety of dive light styles. If your in the market for a primary light and dive in cold water, then a meatier style will most likely fit your needs. If you dive in tropical water or are interested in a backup light, then a smaller, less powerful light will do. There are also lights that you can affix to your tank, allowing your dive buddy to easily spot you while underwater, even in murky water.
If you plan on using your dive light for spotting items and sea life that are tucked away in crevasses or to light your way through a cave or wreck, then you definitely want a steady beam of light.. If a light offers a broad beam of light, it will aid you with general vision while underwater. If a light offers a narrow beam, it will offer a brighter light than a broad beam and will help you see into cracks and the nooks and crannies that are frequently found at depth.
Strobe lights are generally used for underwater safety. They help you identify where your dive buddy is located, even when the visibility underwater is less than ideal. Many dive strobes can be attached to your tank, either around it or at the stem.
When it comes to batteries for your dive light, there isn't a wrong choice. The light manufacturers decide if their lamps use alkaline, NiCad, etc., so you really don't have to worry about that decision. The main thing about batteries is keeping an extra set in a waterproof container in your dive bag. Also, test your light prior to entering the water to make sure the batteries are in proper working order.
If you're concerned about waste, then using rechargeable batteries will ease your ecological conscious. The two downfalls to rechargeable batteries are they are more expensive than disposables and they slowly diminish in quality after each charge. Therefore, as they age, the longevity of the charge will shorten. Disposable batteries are less expensive than rechargeable batteries, but they always fresh when taken out of their packaging; they do, however, carry an ecological downside because they are not biodegradable.
Keep at least one set of spare batteries in your dive bag (within a waterproof container) at all times. You never know when your batteries will decide to go on strike. Also, make sure you know which type of batteries your light uses.
If your bulb is burned out, your dive light is useless no matter how many backup batteries you have on hand.
Keeping your scuba light on a leash will keep it from becoming treasure for a future diver to recover. There are a variety of lanyard styles; most clip to your BCD and tether to your light by attaching to the wrist lanyard or an anchor point.
Some people, especially cave and wreck divers, prefer attaching their dive lights to the back of their hands or atop their helmets. These mounting options keeps their hands free to perform other tasks, which is especially important in tight diving conditions.
The last thing you want to do is find out on the beach or dive boat that something is wrong with your gear, and not have a way to fix the problem. By carrying a save-a-dive kit, you can still safely enjoy your dive or snorkeling adventure just like you planned.