Zeiss C Sonnar rendering across apertures

[mfogiel]

I really like the C Sonnar, and I think to use it best one has to understand its characteristics, Carl Zeiss marketing people have done a lousy job here - instead of playing this lense's winning card, which is its particular optical construction and the resulting rendering, they've publicized it as a "reporter" lens - sort of cheaper Summilux - which obviously the C Sonnar is not. Later they explained it was an "artistic lens" without adding much more...

Considering that the questions relating to this lens come up often, I've decided to show the results of a fast test I had done for my own use: no test charts, no tripod, no pretending the results are gospel... I use this lens to shoot handheld portraits in available light, and this is exactly what i did - a series of shots from F 1.5 to F 8 with my usual film (XP2), very little post processing and next to no sharpening, to transmit the lenses characteristics as much as possible.
I'd like to thank my friend Giuseppe who lent himself as a model during a brief visit at a photo exhibition in Corso Como 10, Milan.

Here's the link to the photos:

http://www.flickr.com/photos/59177039@N00/sets/72157600947495044/

 

[goo0h]

Thanks! This is very helpful!🙂

 

[payasam]

This is the sort of test which can have practical value.

 

[kshapero]

Excellent, what I have been saying along. thank God, there a few lens' out there willing to be different.

 

[Avotius]

hm...I wodner how hard it would be to buy a sonnar here in china then have it adjusted, or if I could buy one somehow from the factory that is already adjusted and have them ship it to me...

 

[ferider]

Think carefully before you adjust it. Up to f5.6 the focus shift is about
half the DOF. When you have it adjusted it means that for any
aperture larger than f1.5 you will be at the limits of the DOF window.
You will have to compensate.

Even though my lens could be adjusted for free, I keep its as is,
maximum sharpness and a reasonable DOF window at f2.8
makes a lot of sense. It is very usable at 2.8 like this.
And at f1.5 you just move forward a little (6cm at closest distance).

Thanks for the test, mfogiel.

Roland.

 

[FanMan]

are you really really sure that the new lenses are adjusted??

 

[FanMan]

Think carefully before you adjust it. Up to f5.6 the focus shift is about
half the DOF. When you have it adjusted it means that for any
aperture larger than f1.5 you will be at the limits of the DOF window.
You will have to compensate.

Even though my lens could be adjusted for free, I keep its as is,
maximum sharpness and a reasonable DOF window at f2.8
makes a lot of sense. It is very usable at 2.8 like this.
And at f1.5 you just move forward a little (6cm at closest distance).

Thanks for the test, mfogiel.

Roland.

same for me - will keep it as it is.

 

[Mario Mazariegos]

Hello....

Hello....

I will keep my sonnar as it is also, its a great lens without the mods already!

 

[foto_fool]

mfogiel - thanks for confirming my preconceptions. My Sonnar is PERFECT as delivered - as god and Zeiss intended. Thank you very much.

- John

 

[sirius]

Nice test, it's very helpful and informative. Thanks!

 

[elude]

If I buy such a lens my purpose is to use it at 1.5 and 2. Otherwise I would get a Planar or a Voigtlander. So I think I'll get it fixed. If I need to close a bit I would never need a lens that expensive in the first place... It's special, so I'll get it fixed.

 

[the_jim]

Even though it's not sharp on his eye at 1.5, it has a really charming quality. I can't stop looking at that shot. I don't think this kind of dreamy 'airyness' would work for every photo, but it's amazing here.

 

[ferider]

It's really pretty easy to correct for the focus shift of the lens optimized
for 2.8. The lens behaves almost identically at f1.5 and f2. To correct
for the shift at those apertures you can:
- at closest distance shift is 6cm. So, for example, you can just focus on the ear instead of the eye in a typical portrait situation.
- use the DOF scale, shorten the lens by using an imaginary f2.8 DOF mark (on the right of the infinity mark). Like if you were shooting Infrared.
- if you use a newer M2 or M3 you can use half of the lower DOF mark (designed for f5.6) in the camera's patch.

It doesn't need fixing since it's not broken. It behaves like classic Sonnars wrt shift, except the shift
is more visible since the lens has more contrast.

Roland.

 

[elude]

Yes but what about the shift when the subject is at, let's say 2meters. I guess you can't focus at all.

 

[ferider]

Yes but what about the shift when the subject is at, let's say 2meters. I guess you can't focus at all.

Like I said, use the DOF scale or the M3 DOF mark - this is independent of
distance.

Roland.