The UK Light Cannon is a pistol-style dive light.
The Underwater Kinetics, or UK, Light Cannon 100 is a pistol-style underwater flashlight with an HID bulb, powered by eight C batteries. For the underwater videographer, the advantage of the UK Light Cannon is that its HID bulb puts out plenty of natural-looking light, as opposed to the harsh, sterile white light of LED dive lights. Even so, making good use of that strong, natural lighting for shooting underwater demands some knowledge of underwater photography technique.
Instructions
1. Check the bezel's tightness before entering the water. You want the bezel, or the cone that contains the bulb and reflector, snug against the body of the Light Cannon, but not over-tight. Screwing the bezel too loosely admits water and ruins the dive light, while screwing it on too tightly damages the o-ring sealing the dive light and opens the door to seal failure in the future.
2. Push the trigger of the Light Cannon up and in to unlock it. Turn the trigger counter-clockwise to activate the light.
3. Hold the dive light in your free hand -- the one you are not using to shoot video -- out and away from your camera, and point it at the video subject so the light strikes it at an angle. This causes backscatter, or light reflecting off particles in the water, to reflect back toward the dive light and away from your camera lens.
