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 in lens aberrations when focusing near/far. The second aperture stop is varied as the lens zooms.

Some of our articles may include affiliate links. If you purchase through these links, we may earn an affiliate commission at no extra cost to you.

Comments are closed.