The art of underwater photography is only carried out using special marine digital cameras operated by professionals from many scientific disciplines. Using an marine digital camera requires skill as you are operating in a foreign environment Many waterproof cameras are ok but they cannot be submerged for more than a meter below the surface of the water
Buying one of those marine digital cameras isn’t really likely but you could buy one of the cheaper options if you are only going below the surface for a short while and not to deep.
You see, water pressure is the real problem for these cameras as well as water leaks Of course quality camera manufacturers have overcome this problem by creating watertight plastic cases that encompass the digital camera. Cases like this, inexpensive in comparison to a real marine digital camera, can for a while make you believe that you too are some kind of underwater photographer.
There are a few things you need to be aware of if you are taking photos underwater.
The water has a strange effect on light as I am sure you have experienced from time to time; it is called diffusion and the deeper you dive the more this distortion takes place. direct result of diffusion; a problem that can be overcome by changing the white balance settings. This diffusion effect also magnifies the image to give the impression the zoom function was used. To ensure the correct image will be taken you will have to pay a little more attention to the shot you are taking.
You don’t want to have a camera that leaks when you go underwater so before you dive, check that the case is waterproof by holding it below the surface for a few seconds. Especially check the seal to make sure that a grain of sand or even a hair hasn’t broken the seal. Small silica gel packs can be useful if they can fit in the case without causing an obstruction.
Optional lenses are often available so if you can add these to your marine digital camera then do so. It is possible to get really close to some subject for great close-up shots using a macro lens.
Also, remember to always wash of salt when you’ve used it under salt water because if the salts are not washed off, in time they will crystallize; and cause leaks in your camera case. It is not uncommon to experience the odd grain of sand getting into the case which will cause problems later on so rinse the case with a flow of clean water.
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