jlbruyelle
Member
The 55/2.8 uses floating optics, the 55/3.5 has fixed elements and is optimized for 1:10 images. It's still a sharp lens. I end up using the 55/2.8 more than the 55/3.5.
I have a 55/3.5 and a 60/2.8 AF-D. When I made extensive comparisons to decide which lens I would use for repro, I found that the the 55/3.5 was noticeably sharper at 1:10, and that the 60/2.8 was noticeably sharper at 1:1, so I kept both and use one or the other depending on the ratio.