About Lenses

Digital cameras have one of four types of lenses:

• Fixed-focus, fixed-zoom lenses - These are the kinds of lenses on disposable and inexpensive film cameras -- inexpensive and great for snapshots, but fairly limited.
• Optical-zoom lenses with automatic focus - Similar to the lens on a video camcorder, these have "wide" and "telephoto" options and automatic focus. The camera may or may not support manual focus. These actually change the focal length of the lens rather than just magnifying the information that hits the sensor.

• Digital-zoom lenses - With digital zoom, the camera takes pixels from the center of the image sensor and interpolates them to make a full-sized image. Depending on the resolution of the image and the sensor, this approach may create a grainy or fuzzy image. You can manually do the same thing with image processing software -- simply snap a picture, cut out the center and magnify it.
• Replaceable lens systems - These are similar to the replaceable lenses on a 35mm camera. Some digital cameras can use 35mm camera lenses.

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• Optical-zoom lenses with automatic focus Camera
  
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• Digital Zoon Lens