There are many different designs for zoom lenses, but they all have some basic principals in common. They consist of a number of differently shaped individual lenses or ‘elements’, some of which move relative to one another to alter the magnification of the image without altering the focus.
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How It Works - Zoom Lenses
Posted on Wednesday, June 20 2007 @ 09:03:54 CEST by Thomas De Maesschalck