April 15, 2010

How to Calculate Lens Requirements

Security cameras utilize two basic lens types based on focusing parameters. These are called fixed lenses and varifocal lenses. Fixed lenses have a “fixed” focal length while varifocal lenses have a focal length that can vary. A more familiar term used for electric powered varifocal lenses is a “Zoom” lens; we will “focus” (pun intended) […]