Calculate Sensor Size
This calculator will return the size of a sensor based on the true focal length of a lens and its 35mm equivalent focal length.
The manufacturer's website will usually have the specifications needed to complete this form. The true focal length of the lens is usually written on the front of the digital camera's lens. The 35mm equivalent focal length is available from either the camera's documentation or the manufacturer's website. For example, the Nikon Coolpix P7700 zoom lens begins at f=6mm which is advertised as a 35mm equivalent of f=28mm. The iPhone 5 begins at f=4.1mm and is advertised as a 35mm equivalent of f=33mm.
NOTE: if the sensor is a 4:3 ratio then there really is no 35mm equivalent and this calculator will return a slightly different size than that which is actually in a 4:3 sensor camera. 35mm is a 3:2 ratio.
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