Convert Digital Camera Zoom to Binocular Power
An explanation and how to convert
The pictured digital camera was purchased because it has a 7x zoom, which I thought made it as powerful as my binoculars. In reality it did not seem to magnify like my binoculars. Now I know why.
The 7x is the result of dividing the small focal length number into the large focal length number giving what I think is meaningless result. In the case of the Nikon 6100 5 divided into 35 results in 7. (what the 5 and 35 actually represent is a whole other story)
To roughly convert to magnification like we know it divide the focal length by 50 and multiply the result by a brand specific factor. For Nikon and Cannon it is 1.5, for Panasonic 2. So this camera has a large focal length of 35 so 35 divided by 50 times 1.5 equals 1.05. Actual experiments seems to verify a magnification “power” much nearer 1 than 7.
The method described should yield a magnification close to reality but likely is not perfect. The factor described relates to sensor size and I can’t imagine a manufacturer using 1 size sensor in all its cameras.