Diver Propulsion Vehicle Training

We’ve all wanted to see more on a particularly spectacular dive. With a diver propulsion vehicle (DPV), you can cover far more territory. But what exactly is a DPV, and what sort of training do you need to successfully use one?

What is a diver propulsion vehicle?

DPVs come in many different models, sizes and capacities. Their main objective is to propel you through the water while you hold onto the machine. DPVs allow you to cover far more distance than just through kicking so you can explore large areas while conserving your air. Obviously, you must still pay close attention to your air consumption and no-decompression limits. A DPV usually consists of a pressure-resistant watertight casing containing a battery-powered electric motor that drives a propeller. The propeller must not harm the diver, diving equipment or marine life.

The PADI DPV specialty

If you’re at least 12 years old and a PADI (Junior) Open Water Diver or higher, you can enroll in the PADI Diver Propulsion Vehicle course.

You’ll make two dives and learn:

  • How to maintain your DPV
  • How to plan dives, including procedures for staying with your buddy
  • DPV-handling skills, such as making proper descents and ascents
  • Potential problems and ways to deal with them

DPV etiquette

DPV operation requires more situational awareness than simply swimming. Operating a DPV requires simultaneous depth control, buoyancy adjustment, air monitoring, and navigation. Buoyancy control is vital for diver safety. Depth changes can occur rapidly when using a DPV, so be cautious when descending and ascending. Generally, you should not use a DPV for these maneuvers.

Be careful around your buddy and other divers using DPVs. Although speeds aren’t great, a diver and vehicle have a lot of mass and impacts can cause injury.

Be courteous to other divers. They might not particularly like a DPV’s sound and vibration, especially when it scares away the critters they like to watch or photograph. If others in your group are not using a DPV, try to stay away from them and go a separate direction.

Always stay with your buddy. It can be exciting to fly around a dive site, but don’t leave your buddy behind. Keep a close eye on each other and know that sometimes one DPV can be slower than another. If you’re using a faster DPV, you may have to wait for your buddy to catch up. If your DPV fails during the dive, you can tandem dive with your buddy back to the boat.

Wildlife interaction

You must be considerate of the aquatic realm when using a diver propulsion vehicle. Lots of small marine life is very well camouflaged and tries to stay hidden. When you’re moving fast on a DPV you can frighten some fish and other marine life if you get too close.

When riding your DPV, be cautious around aquatic organisms and shipwrecks, just as you would without a DPV. Keep plenty of space between you and the reef or the shipwreck you’re exploring.

Avoid touching and disturbing the bottom. Silt decreases visibility and harms aquatic life, particularly corals. It can also clog and damage the propeller.

Pay attention to your fin tips so you don’t accidentally drag or kick anything. You and your buddy should always pay close attention to environmentally-friendly techniques and avoid disturbing or damaging aquatic life.

When I’m using a DPV and I see something cool, I stop the unit and signal my buddy to do the same so we can watch the marine life without scaring it.

Enjoy the ride

With simple dive etiquette and marine-life awareness, DPV diving can be a unique and fun experience. It allows you to really explore the topography of an area and makes for a great dive when exploring walls, reefs and wrecks. Many dive companies allow you to rent DPVs, but we highly recommend signing up for a training course first to learn proper use and safe techniques.

For more information on DPV training at Stuart Cove’s Dive Bahamas, click here.

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How to Identify and Photograph Corals

Underwater photography tends to favor megafauna like sharks, whales, and dolphins, or macro critters like nudibranchs and shrimp. Photographers often overlook corals, which are also living animals. But learning how to identify and photograph corals can be just as exciting as snapping images of fish. It’s also the best way to identify and learn more about each species. (See our guides here and here for more tips on Caribbean coral identification).

Corals, for the most part, stay in one place. This, of course, makes them easier to photograph than fish. Taking pictures of corals is an excellent way for novice photographers to get familiar with their camera settings and start learning how to use external lights. Bigger and better colonies await more advanced photographers at each new dive site.

Checklist for coral photography

If your goal with coral photography is to identify each species, there are a few key shots you don’t want to miss. Begin by identifying the coral’s genus level. For example, learn to spot Acropora corals before trying to tease apart each species.


Scale

The scale of the coral, and particularly the corallite’s size, are important for narrowing down species, so include something in the photo to determine scale. A rough estimate of size will do for most corals, although you should sometimes use a ruler for millimeter accuracy. If you don’t have anything with you to include in the shot, wait until a fish swims by. Take a picture of the coral with the fish in the shot and then one without the fish. This can give you a rough estimate of the size which will be enough for most coral species.


Close-up

As with all underwater photography, you want to be as close to your subject as possible without disturbing or touching it. Underwater objects appear larger, so be sure to get up-close for the best shot. Play around with the macro setting on your camera.

A good coral photo is one that showcases all the polyps and tentacles. This really brings a coral photo to life. Up-close shots of corals feature intricate details that are hard to discern with eyes alone. You will be amazed at how a coral looks once your camera magnifies it.



Polyps

As you look closely at corals, you will see that each one has corallites, valley, walls, and polyps. You can read more about coral biology here, including important terms for coral identification.

Thousands of tiny polyps or a single large polyp can make up a coral. Some of the large-polyp species like Mussa or Scolymia can have quite an intricate display of colors. If you have an external light, try snapping a few shots of these corals with and without your light to see how bright they can be.

Polyps can be the same or different colors than the coral colony. To take your coral photography to the next level, look for polyps that are a different color than the coral. And look for polyps that have more than one color, or brightly colored tips.


Observation

Nothing can replace spending time underwater looking at corals. The more you search for corals, the more new and interesting species will stand out. Instead of spending your dive swimming quickly along the reef, stick to a small area underwater and take a few minutes to observe each coral.

If you’re diving with a shop, ask if they allow diving unguided buddy pairs, and then request a dive at an easy-to-navigate shallow reef. Once the boat is anchored or tied off to a buoy, drop down and stay near the line with your buddy until the rest of the group returns. This will give you an entire dive just to observe corals at your own pace.

Online resources

One of the reasons we love coral photography is being able to identify each species once we’re done diving. If you have diligently taken a few colony shots and close-ups of each species, you can use online resources to help with identification. Note that corals are regional animals, so pay attention to where you saw each coral.

The Australian Institute of Marine Science (AIMS) features informative coral sheets on their website, as does Corals of the World. These online resources are sorted by region and species so you can look for corals either way.

Next time you head out on a dive, pick up a camera to start photographing and identifying corals.

By Nicole Helgason

Nicole Helgason is a PADI Dive Instructor with nine years of professional dive experience. She has taught scuba diving in Canada, Dominican Republic and Indonesia, and has managed dive centers in Mozambique and Baja, Mexico. Nicole has a bachelor’s degree in coastal geography from the University of Victoria and is passionate about coral restoration and coral reefs. She has a website, Facebook, Instagram and Twitter accounts.

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