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Genres in practice3 min read

LESSON 51

Underwater basics

Colour loss, housings, and getting close.

IN THIS LESSON

  1. What changes underwater
  2. Housings and ports
  3. Strobes and backscatter
  4. A short timeline
  5. In practice: start shallow

What changes underwater

Underwater photography means making pictures beneath the surface, while diving, snorkelling, swimming, or with remote and automated cameras. Subjects include fish and marine mammals, wrecks, caves, reefs, plants, rocks and portraits of other divers. The main obstacle is the loss of colour and contrast. Water absorbs the longer wavelengths of sunlight, red and orange first, so even to the eye everything turns blue-green with depth. The loss also grows with horizontal distance, so subjects further from the camera look colourless and indistinct even in water that seems clear. Particles in the water scatter light and soften detail.

Housings and ports

Some cameras are built for water. The first amphibious camera, the Calypso, was reintroduced as the Nikonos in 1963, and Nikon ended that series in 2001. More often, an ordinary camera goes into a housing with controls that reach its buttons, sealed with silicone or other O-rings; high-end housings double the rings on critical controls, because a leak can destroy the camera. A flat glass port distorts the image through refraction, especially with wide lenses, so wide-angle work uses a dome port. Photographers mostly choose wide-angle or macro lenses, because both focus close, and a shorter distance means less water between lens and subject.

Strobes and backscatter

A flash, called a strobe underwater, puts back the reds, oranges and yellows the water removed, and adds shadow and texture. It brings a problem of its own. Backscatter is light reflected from particles in the water, which shows as bright dots in the picture, and even water that looks clear contains a great deal of them. The source's advice is to place the strobe away from the axis of the lens, so it lights the subject but not the water directly in front of the camera. A built-in flash sits too close to the lens for this and is often too weak.

A short timeline

In 1856 William Thompson made the first underwater pictures with a camera on a pole. In 1893 Louis Boutan photographed while diving in standard diving dress at Banyuls-sur-Mer, and developed an underwater flash. In 1914 John Ernest Williamson made the first underwater motion picture, in the Bahamas. In 1926 William Harding Longley and Charles Martin took the first underwater colour photographs, using a magnesium-powered flash. The Rolleimarin housing for medium format, developed at the request of Hans Hass, was first sold in 1954.

In practice: start shallow

This section is working practice. Learn buoyancy and safety first; no picture is worth a risk, and you should dive only within your training. Start by snorkelling in shallow, clear water on a sunny day, where natural light still carries colour. Get close, then closer: fill the frame from a short distance instead of zooming. Shoot slightly upward toward the surface for contrast. Set a custom white balance at depth, or shoot RAW and correct afterward. Never touch or chase marine life, and keep fins away from coral. Rinse the housing in fresh water after every dive.

Try it today

  1. 01Test a housing or waterproof camera in a bath or pool before going to sea.
  2. 02Snorkel in shallow water in sun and shoot the same subject from one metre and from three metres.
  3. 03Compare how much colour survives at each distance.
  4. 04With a strobe, shoot once with it next to the lens and once held out to the side.
  5. 05Look for backscatter dots and note which position avoided them.