Focus Past Infinity?

[prime]

I'm noticing that some of my manual lenses are focusing beyond infinity. Is that a defect in the lens, the mount, or business as usual? I've found "true" infinity focus just short of infinity (at normal temperatures in the middle of the aperture range) on both an old lens with an adapter and a new voigtlander .95 that is native to m4/3.

 

[wbamb83392]

Many lenses go "to infinity, and beyond!" because the only way to be certain the lens is focused at infinity is to go slightly beyond and back again.

 

[Svart]

my lenses can also divide by zero.