Originally Posted by alexandru_voicu
Did I hear something about focus shift?
I must admit, THAT I'm really tired of. I spent ten years of my life trying to compensate for focus shift. I was hoping that Nikkor lenses suffer less from this affliction. If I were a lens designer, my first commandment would be: thou shall not shift.
Alex, I can completely understand your frustration about focus shift. It is indeed an ugly effect. I hate it!
From a physical point of view, generally all lenses have this effect. But it is possible for optical engineers to correct this optical "error" to a degree that it is not visible / significant anymore.
For example Zeiss has corrected their Otus and Milvus lenses in such an excellent way that there is no visible focus shift.
Concerning Nikon: Unfortunately some lenses suffer from focus shift, but other Nikkors don't. The same is valid for the current Sigma "art" lenses.
So you have to look at the specific lens in detail, whether it suffers from focus shift or not.
Concerning current 50mm lenses for Nikon: The Zeiss Milvus 1.4/50, Milvus 2/50 and the Nikkor AF-D 1.8/50 and former AI-S 1.8/50 (long barrel version) fortunately don't
suffer from focus shift.
The Sigma Art 1.4/50 and the Nikkor AF-S 1.8/50G do show some focus shift.
But fortunately the Nikkor has only some very low/slight focus shift at very short distances (0.45m - 1m). In most situations you won't have any problems.