Fine detail is recorded with good contrast but soft edges. This recording capacility holds on axis and only slightly drops in the field. Extremely fine details are just visible, but it depends on the film if you can see them. Stopping down improves the contrast and the recording of extremely fine detail. The edges of outlines stay a bit soft.
Higher contrast give the extremely fine detail more clarity and sharper edges.
Astigmatism is visible which softens the finest possible texture details. Stopping down brings in the extremely fine detail recording with clarity and high edge contrast. It is questionable if one can see it it in everyday picture shooting. This lens is often praised for its image quality. In comparison to the 6 lenses evaluated here, there is not even the idea of a contest.