All non macro lenses are designed at infinity, the picture quality
(most common is resolution and distortion) usually drop when focusing
distance reduced. The close focus correction mechanism in Zuikos are
having a floating rear element group which moves during focusing to
make optical corrections. Even two lenses has same closest focusing
distance but the performance of the one with close focus correction
will perform better. I have no idea on which focal rage it actually
matter and it will also vary with lenses, but the close focusing
mechanism in Zuiko work from closest range to infinity. Perhaps
starting from 1:40 you will see the different.
I have not technically compared all lenses, but the 50/3.5 and 21/2 at
around 1:15 and F4 is much better than all other 50mms I have tested.
The 85/2 is obviously better than the 100/2.8 in close up. I don't
know if a heavy stop down will reduce the different.
C.H.Ling
Thomas Müller wrote:
>
> Hi Zuiks,
>
> I have got a technical question. Only now (I am really ahead of time
> here.) I noticed that some lenses like the 2.0/28, 2.0/24, 2.0/21,
> and the Macro lenses have floating elements for close-distance
> correction. The 2.0/35 does not have it. Still the 2.0/28 and the
> 2.0/35 have identical minimum focus distances. Mmmmh, I am wondering
> what that means?
>
> In which focal range does it actually matter whether the lens has
> floating elements or not?
>
> Thanks and greetings, Thomas
>
> P.S. This is the second try. I think it did not get through the first
> time. I hope it is without html.
>
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