I agree with Chuck.
Please look at these A7-Zuiko pictures (many with 21mm 3.5 and 35mm shift)
of Rotterdam and tell me why I shouldn't be happy with them.
Of course, modern lenses are generally better wide open and corrected, but
also often bigger and heavier. The performance of the Zuiko's is still
nothing to be ashamed of (I think). I do have an issue with my 18mm which I
never noticed on my Canon OM-6D, but hey, my keeper rate has dramatically
increased with the A7.
Don't worry, be happy (with your Zuiko's)
<https://www.flickr.com/photos/78837261@N08/sets/72157648933246533/>
2015-03-17 1:05 GMT+01:00 Mike Gordon via olympus <olympus@xxxxxxxxxxxxxxxxx
>:
> I am very comfortable carrying my OM bodies and Canyon digital back but
> prefer to lug less heavy stuff these days.
> Thus my toe dip into MFT and possibly sony in the near future. I really
> like the new high performing lenses these days
> but miss some "rendering character" of my lenses built for film. Many
> newer ones are very sharp inded but tend to have
> a sameness about them and fair to middling bokeh---this is a vast
> generallization with some glaring exceptions. Perhaps the aspheric elements
> play a role. Anyway I enjoy the character and adapting of my old friends.
>
> I do not have a good handle on the complexities of determing how to
> achieve optimal performance. The adpater quality/precise dimensions seems
> to one variable. (Expense did not guarantee a good match for a lens in
> Roger's tests at lensrental)
>
> http://www.lensrentals.com/blog/2013/09/there-is-no-free-lunch-episode-763-lens-adapters
> This is not a trivial issue for wide angles and seems to be especially
> importnat for those with floating elements (may interact with sensor stack
> thickness) Minor offsets in thickness effect the peripheral rays in a
> nonlinear way and not corrected by depth of focus considerations. The
> corners just become lousy. Some lenses seem to developefield curavture.
> While the inherent amount of curvature in the optic will certainly vary
> from lens to lens, moving a given lens forward or rearward will have a
> non-linear (curvature is non-linear) relationship change between the
> distance to the center of the film plane vs. the distance to the corner.
> Shimming the adapter to get infiinty spot on corrects this. I don't
> understand this fully. Dr. Focus was skeptical of any serious issue.
> Another issue is the stack thickness already discussed and posted
> previously.
>
> http://www.lensrentals.com/blog/2015/01/a-thinner-sensor-stack
>
> There is now a commercial correction for this!! Some WA's as long as
> 28mm are affected.
>
> http://www.kolarivision.com/thinfilterconversion.html
>
> From Dr. Nasse at Zeiss--mostly an issue on tangential plane:
>
> From Nasse:
>
> "Lenses with a very large beam tilt react in a much more sensitive manner
> to a change of refractive index in the image space caused by filter plates
> in front of the sensor (such as low pass and IR-blocking filters). If the
> filter plate is not considered in the design of the lens, the edge
> definition will suffer. The effect of the additional path through the glass
> grows exponentially with the beam inclination. A Distagon which never
> achieves more than 20° beam tilt in the corner of the image reacts more
> tolerantly than a symmetrical wide- angle lens, which might reach a 45°
> tilt. This is why filters in digital Leicas are very thin – to remain
> compatible with older optics. If the filter is significantly thicker, the
> contrast transfer for the image edge becomes worse for tangential
> structures. In the graph of the curves, this looks like the old retrofocus
> lenses but is caused by astigmatism rather than lateral chromatic
> aberration. The focus is shifted to greater distances for tangential
> structures by the additional path through the glass. If the best edge
> definition is to be achieved, then all that can be done is to stop down
> further."
>
> I wish I had a good handle on these issues.
>
> Adaptation bewilderment, Mike
>
>
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