Nikon Chat: Nikon Digital Cameras and Equipment

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How do you know what the manification is an SLR lens?

I'm used to fields that are the sense of 6X55 6 increases in capacity, and a 55mm lens. In a 18-or 55-200mm 55mm SLR lens is not this the case? How I can find the expansion? (I'm looking for Nikon Nikkor 2) Even manufactureres websites, I am having difficulty finding the zoom. Thanks in advance for your help!

In zoom lenses, the "x" number, such as in "3x zoom," it refers to the increase compared to a "normal" lens. It refers to how many times and the focal length Long zoom range compared to the shortest. In other words, how many times closer is the longest telephoto zoom position compared with wide-angle flea. To calculate the capture of "x", simply divide the longer focal length for short. To use the example: 18-55mm is a target 3x zoom 3.6x. Is a 55-200mm zoom lens. As for the actual magnification of an SLR lens, calculate the focal length compared to a "normal" distance Lens focal. For 35 mm SLR camera film, a "normal" lens is considered to be of 45 mm. A 90 mm (telephoto) lens reflex used in a 35mm film SLR makes the image twice the size of a camera lens of 45 mm, so you could call that a 2x magnification. For Cameras Digital SLR (DSLR), the size of a display device inside the camera is usually smaller than a film frame of 35 mm, so a shorter focal length of 45 mm is a normal lens for most digital SLRs. There is a factor used to multiply the lens focal length to compare enlargement of the image in digital SLRs particularly with respect to the same focal length lens used in a 35 mm SLR camera. It's called the "culture factor "or" scale factor "or" form factor "or" focal length multiplier. "