With the Canon WP-DC7 waterproof case for the PowerShot SD900, you can use your PowerShot SD900 digital camera to take underwater shots at depths of up to 130' (40 m). Of course it's also ideal for taking worry-free pictures in the rain, at the beach, or on the ski slopes.
You can use your camera's internal flash for lighting purposes. Or, use the internal flash to trigger a slaved external strobe like those made by Fantasea, Sea & Sea, Ikelite, Sunpak or Sealife. The camera has a underwater white balance setting for available light photography.
