Northlight has uncovered a patent relating to a zoom lens design with two aperture stops. Within the patent are two different optical formulas, one for an EF 16-35mm f/2. 8 and another for an EF 24-70 f/2.
8. According to Northlight: The aim is to produce a zoom lens with constant minimum aperture, but having small variations Read more. . . . canonrumors.com
2018-6-29 19:43