Most cameras come bundled with an inexpensive “kit” lens. These vary in value underwater, but generally aren’t wide enough, focus close enough, or offer the best sharpness to be used well underwater. The extra expense of extensions, gears and ports can make these “inexpensive” lenses poor investments in the long run. Many new underwater photographers end up selling them after a short while after being disappointed with the results.
Underwater we generally want three general focal length ranges of lenses; all with the idea of getting as close to our subject as we can. Water absorbs light, color and clarity; eliminating as much of it as we can gives us the best results.
Those ranges are ultra-wide (usually fish-eye), mid-range zoom, and macro. Ultra-wide fisheye lenses yield the best corner sharpness, due to the loss of one-third of our field of view underwater, they become rectilinear. Their “round” corners match the dome ports that replace much of this loss of field of view. Normal wide-angle rectilinear lenses, as great as they are above water, generally don’t focus as close, not have the corner sharpness we desire, due to refraction.
For more information about what lenses we recommend please see our Guide article in our Educatiion section of the store site.
