Sigma fisheye lens 8mm f/4 was released in the early 80s. The lens is covering a 180 degree image on a 22mm circle. apertures f/4 – 22 and a 20cm closest focus distance. Uses the same 22.5mm inner filters, you have to separate the lens in two parts to access them.
I’m looking forward to some info on this lens history. First of all the exact market introduction date…
- Sigma UK website has a beautiful information sheet.