What does it look like to mount a 7.5mm fisheye lens on a smartphone?
Look how wide it is!
Full screen fisheye view with a field of view of 238 degree.
The barrel distortion on a fisheye lens is very normal. The black circles around the edge of an ordinary fisheye lens has always been a problem, Thanks to Kase as they offer a 7.5mm fisheye lens that has no vignetting!