Zoom Lenses for Digital CamerasYou should be aware though that one 3x zoom digital camera can offer a different amount of zoom to another camera that is also described as having 3x zoom.
All cameras have something called a focal length. This is true even for a camera without a zoom lens. The focal length is the distance from the optical center of the lens to the camera's focal point. For digital cameras the focal point is located on the camera's sensor. For a camera without a zoom lens the focal length is said to be fixed as the lens never changes position. When using a zoom lens the position of the lens changes as you zoom in and out. As you zoom in the focal length increases. As you zoom out the focal length decreases. Therefore the focal length of a camera with a zoom lens is given as a range of two figures. The 105mm is the focal length when the zoom is fully extended.
By dividing the longer focal length (105mm) by the shorter one (35mm) we can work out that this camera has a 3x zoom lens.
Cameras offering a wider picture angles are said to have a wide angle lens. The camera with the focal length mentioned earlier of 35 - 105mm can zoom in closer even though both cameras have a 3x zoom lens.
The Nikon Coolpix 5400 is considered a wide angle digital camera. Its focal length ranges from 28-116mm. It is normal to see two zoom ratios quoted for a camera. One is for optical zoom already discussed the second is for digital zoom. Digital zoom is completely different to optical zoom. Rather than using the lens to zoom, digital zoom is carried out by software inside the camera. For example a camera with 10x optical zoom and a 4x digital zoom can give a combined total of 40x zoom.
Check out my other guide on nikon digital camera
summarized from cameras.co.uk
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