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Digital Camera > Digital Camera Know-Hows > Relationship between Lens Magnification and Lens Length (mm)
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A digital camera at its widest angle is said to have a 1x zoom. However, since the widest angle will vary with almost every camera, an absolute millimeter value for a 3x zoom is impossible. If the widest angle is equivalent to 35mm, 3 times that would be 105mm. If the widest angle was 25mm, it would be 75mm. Even though the amount of magnification is the same, images taken at 105mm and 75mm have very different viewing angles and produce very different images. Please use the following chart as reference for the correlation between magnification and millimeters. |
Relationship between Lens Magnification and Lens Length (mm) |
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Don't confuse zoom magnification!
For example, when the term 3x zoom is mentioned, many people confuse this for being three times the power of their normal sight. Actually, the 3x value is calculated based on the widest angle of that camera's lens. The human eye, on the other hand, is approximately 50mm, which when compared to a digital camera with a wide angle of 35mm, is already almost a "1.5x zoom." To prevent possible misunderstanding, be sure to check the camera's widest angle and remember that the camera's 3x magnification starts from that point. |
