Originally Posted by gkopeliadis
If makers could get rid of the SLR on the dSLR there would be great benefit in IQ.
I mean that the mirror dictates the last element of the lens to be some 5cm away from the sensor ( or film). That posses IQ problems to all lens up to 30-50mm, especially at the borders. Remember some large format wide angle lenses that needed the mirror to be locked up all times and had their own view finder? That was the problem they were addressing.
If you move the rear element closer to the film plane, then it creates a new set of problems, most notably vignetting, because the angle of the light hitting the sensor would be more oblique. Therefore doing away with the mirror will not solve any problems. A better solution is to use a fixed pellicle mirror. If the mirror does not swing up, then you can move the rear element closer, if necessary.