Extended Life Replacement Battery BP-727

High resolution, manual focus digitally-optimized fisheye lens HD, super multi-coated optics reduce lens flare and ghosting while ensuring very sharp images Aperture Range, F3.5 ~ 22 12 inch minimum focusing distance for incredible close ups Ultra-wide 6.5mm focal length Minimum Focusing Distance 1 ft. / 0.3m Length 10cm / 4 in. Weight 14.6 oz. (414g) 10 Elements in 7 groups (1 spherical lens) Removable hood allows for full 180° views and stunning panoramics F.A.Q. Problem: Camera shutter does not release when lens is attached Solution: Since this lens is fully manual and does not have CPU contacts, it is not recognized by some cameras. Please switch your camera to M (manual) mode. Problem: Images are too dark Solution: Lower f-stop on lens, and/or lower shutter speed, and/or raise ISO settings on camera. Problem: Images are too bright Solution: Raise f-stop on lens, and/or raise shutter speed, and/or lower ISO settings on camera. Problem: Images are not coming out in focus Solutions:  a. Adjust the focusing distance on the lens to the correct distance.  b. In certain photographic situations, you may find it easier to get focus at f/5.6-8 rather than on f/3.5