03-16-2015, 07:32 PM
Depends what with. Can the design be fixed - yes. Can the lens+sensor interaction be fixed, probably not.
Symmetrical wide angles have exit pupils that are quite close to the sensor. The design itself is okay, even the coverglass is okay, but when the pixels get below some size photons end up crossing the entire photodiode and embedding themselves in the wall of the pixel before they are absorbed. This happens more for longer (redder) wavelengths as the tend to not divert from their original path as easily (see: prisms and rainbows) hence the blueshift/color cast in the corners.
The general consensus in the lens design community (to my knowledge) is that bertele's symmetrical wide angles have been obsoleted by digital sensors, which is a shame because they are often rather beautiful designs.
Symmetrical wide angles have exit pupils that are quite close to the sensor. The design itself is okay, even the coverglass is okay, but when the pixels get below some size photons end up crossing the entire photodiode and embedding themselves in the wall of the pixel before they are absorbed. This happens more for longer (redder) wavelengths as the tend to not divert from their original path as easily (see: prisms and rainbows) hence the blueshift/color cast in the corners.
The general consensus in the lens design community (to my knowledge) is that bertele's symmetrical wide angles have been obsoleted by digital sensors, which is a shame because they are often rather beautiful designs.