Underwater Photography Guide is a great place to compare different underwater cameras. Their website provides articles and reviews on a number of different underwater cameras.
Yes, Olympus does manufacture underwater cameras. They have a wide variety of underwater devices to choose from. They have high-end underwater cameras film loaded cameras and even underwater video cameras.
Underwater photography can be done with most regular camers with a underwater plastic body around the camera or with specific water resistant underwater cameras.
Underwater Cameras
Coach underwater cameras can be used both underwater and above water and under most lighting conditions. There are several different types of cameras to choose from allowing you to get the exact effect you desire.
Yes.
The Sealife Cameras company manufactures specialty cameras that are meant for photography underwater. Most of its stock consists of underwater cameras and their accessories.
Sony is offering a new underwater camera. You can also go to sites like scuba.com to find high quality underwater cameras for cheap. Most major camera brands offer underwater cameras.
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You can get waterproof cameras almost anywhere regular cameras are sold. It may be wise to buy an inexpensive underwater camera just in case it gets lost or damaged. In that case, you can buy one at a store such as Target or Wal-Mart.
When looking to purchase an underwater camera, avoid cameras that focus specifically on the depths to which you can go with it. You might end up paying for a good case but not a very good camera. Check the specifications for motion control as you will be moving around a lot underwater when trying to take a picture. Ask photographers what cameras they use for underwater purposes, and try to find the best deals on what they suggest, or check out the photoblogs of underwater photographers to find out what kinds of cameras they use. When you have a model in mind, research it thoroughly using Consumer Reports or Amazon reviews, and find a price that fits with your budget.
DSLR cameras are supposed to be different than "regular" cameras in the way that they capture exact what you see through the lens. Other cameras can take pictures that end up looking nothing like what you saw through the lens.