Originally posted by luftfluss The counter to that statement would be that APS-C cameras use the "sweet spot" of the film-era lenses, and thus avoid photos with soft edges or corners that many of these old lenses produce with 35mm film or FF image sensors. In that sense, the smaller APS-C sensor is ideal.
I have no personal experience with this, as APS-C is the largest sensor in any of my cameras.
Unfortunately neither do I have any experience.
The 'wander about' lens on my K-30 has been a FA 28-105 lens ever since the K-30 began to suffer Dark Image Syndrome, but I have never used it on a "FF" camera. In fact, I have a collection of lenses that are dedicated to the K-30 {because each has an aperture ring}, but I have never used any of them on a "FF" camera, {most} not even on my "Super Program" 35mm film camera.