The image circle falls off at the edges with digital capture, because of the accuracy of the chip and the fact that the light strikes the sensor at an angle.
The digital lens design is based on the Bathascopic design used mostly for submarine periscope lenses.
S.
Bathascopic principles are applied to periscope lenses only to facilitate celestial navigation whilst submerged. Light ray parallel vertical angularity alteration can only be accomplished under water.
Dave East-Englewood ----------------------- The proof is in the print.
