I was asked for a comparison of Hasselblad lenses at medium and short range. I prepared the short range shots yesterday. The lenses I used were the 180/4, 12o0/4, 100/4 and 80/4.
Of this lenses the 100/3.5 Planar is optimised for long distance work, but not recommended for short distances. The Planar 120/4 is intended for Macro work. The Sonnar 180/4 is said to be tweaked a bit for close up work.
When looking at the corner of the Planar 100/3.5 I saw that the lens was clearly outside it's comfort zone, but it also looked like having significant astigmatism.
In the crops below the Planar 120/4 at f/8 is on the left and the 100/3.5 at f/8 is on the right, both are 1:1 crops of the upper left corners.
Note that the star image on the left side is nice and symmetric, while on the right side it resolves down to pixel level but it is fuzzy in the other direction.
I recalled that Hasselblad used this lens in publication comparing V and H-series lens designs. In that article they have published MTF data for the Planar 100/3.5 at both 1.2 m and infinity.
Here is the MTF at f/8 for 1.2 m focusing distance:
Here we can see that the curves split so tangential and sagittal structures have different planes of focus.
The same lens used at infinity has an essentially perfect MTF curve:
Modern designs often use floating elements where one or more lens groups move under focusing to achieve consistent performance over the focusing range.