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View Full Version : 8mm fisheye vs 7-14mm - field of view


Loup Garou
17th January 2016, 10:22 PM
I have never owned a true fisheye lens and hence the question.

Apart from the obvious difference in the maximum aperture, is there any difference in the field of view between the Olympus 8mm f1.8 Fisheye and the (at its 8mm setting) Olympus 7-14mm f2.8 Pro lenses? More specifically, one looked at a specific scene from the same vantage point, would there be a difference in the image on the screen?

Graham_of_Rainham
17th January 2016, 10:47 PM
An 8mm "fisheye" lens will have a FoV of 180 on the diagonal axis of the frame.

The 7-14 is a rectilinear design that has a FoV of 114.2 to 75.4 on the diagonal axis.
Horizontal 104.3 - 65.5 and Vertical 81.2 - 46.4

On a fisheye lens an horizon or straight line will only be straight when aligned with the axis of the lens. Anything off-axis is distorted (curved)

The 7-14 is very well corrected and straight lines stay straight throughout the frame (with a good degree of accuracy)

Loup Garou
18th January 2016, 09:23 AM
Thank you very much. That is an excellent explanation. :)