The focal length of a 180° fisheye lens is very short - about 8mm and gives an extremely wide
view, but the image it shows has “barrel distortion”. Horizontal and vertical lines bow considerably within the circular
frame. In actual fact the image which it gives is not very far away from what we actually
see. In reality, our eyes have quite a wide perspective but lose a lot of definition at the
edges, which become distorted. With a fisheye lens, the least distortion occurs in the centre of the
frame, so the main subject is best placed there. The fisheye also provides extreme depth of field and no focusing is
needed. Everything is sharp, from foreground to infinity. The front of the lens has a very large diameter and is too large for
filters, so built-in filters are not uncommon.
The weird and wonderful shots seen here were all taken with a 16mm
fisheye. |
