Digital Underwater Photography

Equipment

Cameras

There are two basic types of digital cameras:

1. Point-and-Shoot Cameras—compact cameras are the most common and popular to house. They are great for those who are not sure what to buy and don’t want to invest a lot of money in a camera system that will sit on the shelf most of the time gathering dust. In this category, you can also find the mid-price cameras for the enthusiastic photographer, which includes more advanced features but can still act as point-and-shoot camera most of the time.
2. Single Lens Reflex Cameras—SLR cameras have a variety of detachable or interchangeable lenses and provide very high-resolution images. Another advantage to SLR cameras is lack of a delay when shooting photos.

In addition, there are amphibious cameras that do not require an underwater housing, such as Sea&Sea DX-3100 and Olympus 725SW and 770SW. These Olympus cameras are pressure tested to a maximum depth of 5 metres/10 meters respectively and are suitable for snorkelling more than scuba diving.

Housings

Underwater camera housing is a special case that is camera-specific, is watertight and pressure-tested to be taken underwater and allows you to operate your camera underwater. Most common underwater housings are made from either plastic or aluminium.

Many compact camera makers nowadays build underwater housings for their particular cameras. There are also housing manufacturers that make specialised models for various—usually high-end—cameras, for example Ikelite, Sea&Sea, Subal…

In the past, underwater photographers were faced with extremely limited choices in respect to housings, most of which were extremely bulky, poorly designed and provided limited access to the camera’s controls. Today’s housings are well-designed, compact, rugged, and offer access to all of the camera’s functions. The question is no longer “Can I find a housing for my camera?” but, rather, “What is the best housing for my camera?”

Ports

Having a collection of lenses and being able to take advantage of them often prompts a photographer to buy suitable ports for the various lenses. Ports generally come in three types: standard for normal lenses, domes for wide-angle, and extended for macro. Most conventional lenses will work with a standard flat port. It is only when the photographer decides to take full advantage of extreme lenses that additional ports are needed. The standard flat port will work with a conventional lens, as well as standard wide-angles.

Two invaluable lenses every underwater photographer should have are: a macro and a super wide. But each lens requires a particular port to accommodate it. For these extreme lenses, however, you will need to buy two additional ports.

Macro lenses are typically long and require an extension to the standard flat ports to accommodate the long barrel of macro lenses. In macro photography, where depth of field is extremely shallow, rather than adjusting the focusing knob while trying to capture a skittish subject, it is sometimes much easier to “inch” forward until the subject comes into focus in the viewer. One of the disadvantages of standard flat ports is that they narrow the angle coverage of the lens behind it.

With normal or short macro lenses, the magnification effect underwater brings the subject closer to the lens. But for wide-angles, where the lens is designed to capture a wider view, the reduced angle of the port view inhibits the effectiveness of the lens. In order to overcome this and other limitations, you need to use a dome port. Dome ports are used with wide-angle lenses, which increase the angle of coverage over a standard port. They have four advantages over flat ports:

1. They preserve the angle of coverage of wide-angle lens.
2. They don’t vignette—wide-angle lens behind a flat port may capture the edge of the port and will create a dark ring around the frame.
3. They “saturate colours” to give extremely pleasing results.
4. They allow the possibility of 50/50 photos—images that are half-above, half-below the water.

Strobes

Another essential component of underwater photography is a strobe (basically a flash unit). The strobe supplements the overall exposure and restores lost colour by providing an artificial light source. Strobes help bring back the natural colours to your photographs.

There are two types of strobes:

1. Internal flash that is built into your camera.
2. External strobe, which is a separate unit attached to your housing.

To hold the external strobe (or strobes) in position, you will need a set of arms that can be manipulated to position your strobe(s) as needed.

Please check the Strobes page for more information about strobes.

Colour Correcting Filters

One of the first colours you loose underwater are the wavelengths of reds and oranges. A colour corrective filter is a lens made of coloured glass that screws onto the lens or in front of the housing’s front port. They usually come in a red and orange colour that help bring natural colours back. However, they cannot be used with a strobe. You will have to choose one or the other.

Many manufacturers offer a blue water filter (UrPro) that is designed for depths between 3 to 20m and is ideal between 5m to 10m. For clear tropical waters the filter is usually orange in colour and magenta for green murky waters.

Selecting your Equipment

You might already have a digital camera that you would like to use underwater. You will need to check if an underwater housing exists for your camera. It is recommended that you select your underwater housing at the same time you select your digital camera. Digital camera technology is improving rapidly. Therefore, if you camera is a few years old, there is a good chance, you will not be able to find a matching housing for it.

A few factors you should consider:

1. Are you new to photography in general?
2. What camera do you use on land?
3. How often do you dive? And where?
4. How often do you plan on using your underwater system?
5. How much money would you like to spend?
6. What would you like to do with the photos?

If you are new to photography in general, only dive on holidays and don’t want to spend too much money, a compact camera system should do the trick. You will be amazed at some of the photos these small cameras can take. Keen photographers might find the compact cameras a bit limiting and would prefer a mid-price system, which clearly costs a bit more, but assures very good images (if your photography skills are to match). On the other hand, if you love your SLR land camera and cannot imagine using anything less, are interested in more than merely snapshots of your vacation, dive frequently, get annoyed with shutter delays and don’t care about your children’s college fund, an SLR camera in a specialised housing might be the right for you.

Further Resources

• Andrew Dawson, Getting Started in Underwater Photography on Nature Photographers
• Andrew Dawson, Underwater Housings. This article looks at a few high-end underwater camera systems and might help you select yours.
• Peter Rowlands, Underwater Cameras, on the British Society of Underwater Photographers. An overview of underwater cameras with a good introduction to Amphibious cameras.
• Steve Warren, An Introduction to Digital Photography Underwater. Even though this article is offered by a retail outlet, this article introduces the advantages of digital photography and continues with a good overview of strobes, lenses and major camera brands.