:: 09. Excercise Your Options

In order to overcome these restrictions, various optional accessories handy for underwater photography are sold in the market.

Let's see how these optional accessories will enhance the fun of underwater photography and its possibilities.

Try a Macro Lens

Some optional lenses, such as macro lenses or close-up lenses, allow you to approach closer to subjects to make small things appear larger. You can shoot fingernail-sized subjects at a much larger size with these lenses or shoot images in which the subject appears to float in sharp focus against a blurry background because the lensesÕ depth of field is relatively shallow. Conversely, the lensesÕ shallow depth of field requires discipline and technique since there is less latitude in focussing and it may be more difficult to time shots.

Try a Wide Converter Lens

A wide converter lens can broaden the camera's angle of view underwater, which is narrower than on land because of refraction at the boundary between air (in the lens) and water. This comes in handy when the camera's standard lens by itself requires you to move back to fit an interesting underwater formation in a composition, but the water is too murky for good visibility at that distance. If you attach a wide converter lens, you can get closer to the formation so that the water quality is no longer a limiting factor.

Try an External Flash

An external flash fires in sequence with the built-in flash, which would cause the marine snow phenomenon if used by itself underwater. This phenomenon arises from light from the built-in flash, which is close to the lens, bouncing directly back onto the lens from plankton and particles of sand in the water in front of the lens. To avoid this phenomenon, situate the external flash as far away from the camera as practical and direct its light at an oblique angle to the lens.

An external flash not only provides the opportunity for clear, colorful pictures underwater, it can also be used to create the effect where the main subject is the only thing illuminated and appears to float against a dark background.

This section has been extracted from Canon Japan on how to prepare your digital investment.

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