underwater Photo Course :: (2) Equipment Guide :: Underwater Camera Housings :: Lenses and optics :: Wide Angle Lenses

The first rule of Underwater Photography is get rid of the water! Reducing the amount of water between the subject and the lens gives sharper detail, richer colours, and increased contrastthe difference in desity between parts of an image. High contrast for example denotes larger differences with blacker blacks and whiter whites.. This is consequently one general principal that is important to photographic success underwater. It also explains why the wide angle is the underwater photographer's favorite lens (because it allows the underwater photographer to get a good scale of reproduction at close distances).

Typically, wide-angle lenses used underwater have an angle of view between 90 and 60 degrees. Wide-angle lenses have an enormous depth of field (the zone in the picture that appears in focus) and so are virtually focus free, making them very easy to use and versatile. They are suited to most underwater subjects from wrecks to divers and, because they can focus down to six inches in some instances, they can be used for smaller subjects too.

The majority of wide-angle shots in the diving and other magazines were taken on the 20mm lens in a camera housingA casing or box with waterproof seals designed to contain a camera or other equipment in such a way that it can be used underwater. (equivalent to 15mm Nikonos). A wide-angle lens should be at the top of your shopping list, right after a strobe.

Wide-angle lenses do unfortunately suffer from Barrel DistortionBarrel Distortion is a problem associated with wideangle lenses whereby the image appears distorted outwards., particularly curvature of field, which is especially noticeable at the edges. On land this effect can be distracting, but it is not a disadvantage in most underwater applications as there are not many straight lines underwater to betray the distortions (except wrecks).