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Προβολή αναρτήσεων από Μάρτιος, 2012

The angle of view (in degrees) at various focal lengths

In order to have more control over my panoramas (when overlapping shots), I created this small data table in Excel.




UPDATE: 
I recreated the data tables in Excel.
You can now find more information below:
https://docs.google.com/spreadsheet/pub?key=0AmeXsxxW0BJQdGUwYlpEU3h2OElTQWZCMnBfZjJockE&output=html

Actual magnification of a camera lens

A 75-300 lens is said to have a 4X zoom range, not a 4x magnification.
The 4X zoom range actually means that 300mm is 4X greater than 75mm (75x4=300).
A 30mm to 300mm lens would have a 10X zoom range, but it would not bring anything closer than the 75 to 300mm lens (with a 4X zoom range), since the maximum focal length in both is the same.
It is generally accepted that for a 35mm film camera, a 50mm lens most closely approximates what our eyes see (in reality it should be 42mm - always using the 35mm format).
By dividing the focal length of your lens by 50, you can estimate the actual magnification.
A 300mm lens (on a 35mm film camera or a full frame digital camera) would have a magnification factor of 7X (300/42=7.1).
When used on a Nikon D90 (smaller sensor than a full frame camera - 1.5 crop factor) then you would have a magnification of 11X (300/28=10.7). You could say that a 300mm lens on a Nikon D90 is roughly the same as using a 11X telescope..
A 1200mm scope will have a zoom …