>>2682441I can give you an example. This particular design has an element really close to the E-Mount sensor.
This does not mean every design optimised for E-Mount needs this. But it means there is room for the element to be as close as this, should the need arise.
For this particular design, they found out the lens could benefit.
for other designs, it's not needed.
But lets say you need to design a lens that would fit into Every Full Frame compatible mount in the world. Then you would automatically dismiss the lens design in my picture, and settles for some other design which is significantly different. And you would be forced to do it, whether it's better or worse.
