ZM Planar vs Sonnar C stopped down

[Peter_S]

Hi!

I am aware of the much debated OOF/bokeh/focus shift differences between the ZM Sonnar C 50 (which I own and use a lot for portait/people/reportage) and Planar ZM (which I am thinking about buying) when shot wide open.
Now - what about performance at f/8-f/11? I am primarily interested in across-field sharpeness, crispeness, and microcontrast (and resulting 3D rendering) for landscape when used with fairly high-resolution film like Delta 100, Acros, ATP or Chrome Elite slide film and large prints. I am missing some "bite" in my Sonnar C landscape photos, but that may also have its source elsewhere (film development, light, metering, etc).

Seems, from what I have seen, that the Planar has the edge, but then, shots had different photographers, situations, light, etc.
Any practical experiences?
I was very happy in that respect with the 2.8/25 Biogon (well, the reference I suppose) and 2/35 on both M6 and M8.

[Araakii]

Planar is for you if you are mainly interested in doing landscape work. Sonnar is not meant for that.

[BobYIL]

Peter, around f5.6-11 you can not tell which is which as long as you shoot film.

[redisburning]

Originally Posted by BobYIL

Peter, around f5.6-11 you can not tell which is which as long as you shoot film.

are you speaking from experience? and on the films the OP mentioned?

because on delta 400 I can see a resolution difference at f5.6 between two modern double gauss lenses, and I suspect the difference between the planar and the sonnar would be even more pronounced. I don't have a sonnar to test though.

[BobYIL]

Yes.. I have two C-Sonnars, one is chrome and the other one black. With the Summicron V4 (tabbed but latest formula) I was able to see just a little difference on the corners with Acros, but not with the 50/2 Planar. Larger apertures than f5.6 Planar was sharper and f2.8 on was far sharper.

[Jockos]

Originally Posted by Peter_S

I am missing some "bite" in my Sonnar C landscape photos, but that may also have its source elsewhere (film development, light, metering, etc).

are those sonnar shots compensated for focus shift? Otherwise you'll be "in DoF", but not at critical sharpness right?

[Peter_S]

To clarify - you mean between f/5.6 and f/2.8 the Planar is sharper than the Sonnar C?

Originally Posted by BobYIL

Yes.. I have two C-Sonnars, one is chrome and the other one black. With the Summicron V4 (tabbed but latest formula) I was able to see just a little difference on the corners with Acros, but not with the 50/2 Planar. Larger apertures than f5.6 Planar was sharper and f2.8 on was far sharper.

[Peter_S]

Hm. Never thought about that. If my Sonnar is optimzed for f/2.8. OK, focus shift at f/1.5...but would there be focus shift at f/8 as well, but here covered by DOF?

Originally Posted by Jockos

are those sonnar shots compensated for focus shift? Otherwise you'll be "in DoF", but not at critical sharpness right?

[BobYIL]

Originally Posted by Peter_S

To clarify - you mean between f/5.6 and f/2.8 the Planar is sharper than the Sonnar C?

Between f2.0 to f5.6, all apertures the Planar is sharper at the edges and corners than the C-Sonnar. Since the focus shift continues up to f4 with the C-Sonnar I would not state something concrete about the center sharpness; however @5.6 I could not see any difference worth to mention.

[Peter_S]

Ok thanks!
Perhaps I should clarify. The Sonnar C photos are sharp, they just seem to miss a bit of crispeness. Again, this may have several reasons.

[BobYIL]

Originally Posted by Peter_S

Ok thanks!
Perhaps I should clarify. The Sonnar C photos are sharp, they just seem to miss a bit of crispeness. Again, this may have several reasons.

The Planar 50 is indeed a Summicron class lens as far as sharpness and optical corrections are concerned. The only difference (which is not important for you as you shoot rather B&W) Leica colors are toward cooler spectrum whereas almost all Zeiss lenses toward warmer.

Planar bokeh is not also like the C-Sonnar (overly smooth, exaggerated but abrupt OOF due to one ton of chromatic aberrations). It's better than all Summicrons, rather a balanced bokeh. You may love it too (If you were able to test your C-Biogon then it's closer to it..)

[Peter_S]

OK. Thanks guys. I should perhaps give the Planar a shot after all.

[mfogiel]

The C Sonnar will be as sharp as the Planar only by f 8.0. In any case, it will always have smaller microcontrast, in other words, the image will look smoother, this is why C Sonnar is such a fantastic portrait lens. For landscape, unless you want to make it really impressionistic in appearance, I would definitely go with the Planar.