underwater Photo Course :: (2) Equipment Guide :: Underwater Camera Housings :: Digital Underwater Cameras :: D-SLR Lens Gears

Lens gears are toothed rings that mate up with external controls on a housing to alter the settings (such as apertureThe variable diameter hole used to control the amount of light passing through a lens., zoom, and manual focus) on D-SLR lenses.

These gears either slip on for a tight push fit or are held in place by grub screws. Many lens gears are interchangeable so you don't need to buy one for each lens but continual swapping results in visible wear and tear to your lens that will reduce its resale value. It is much better to buy gears for each lens and leave them on permanently.