? re. 50 planar vs. 50 sonnar

horosu said:
I have just had a look at the MTF of the Nokton (http://www.imx.nl/photosite/technical/highspeedlenses/t003.html) and Sonnar (http://www.zeiss.com/C12567A8003B8B6F/EmbedTitelIntern/CSonnar_1.5_50_ZM.EN/$File/CSonnar_1.5_50_ZM.EN.pdf) and to me they are quite similar wide open...

One thing that attracts me to the Sonnar is its beautiful (to my eyes, at least) color and texture rendition...It is sharp without being aggresively so ("clinical"?). It almost looks paint-like.
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Thanks for posting the links, Horosu. 🙂

I cannot find this page on Erwin's site. I can access it from your link, but not from the index on his site. How did you find it?

I wonder where he got the MTF graph for the Nokton. I've never seen one published anywhere before. I wonder if he tested the lens himself or if it was provided by Cosina.

The differences between the calculated & measured MTFs of the Summilux ASPH are striking. There should be a lesson there.

I see the results with the Sonnar the same as you do. Beautiful is the word for it. 😎
 
You can find it on the right-hand side of Erwin's home page (www.imx.nl), the topic being "development of high-speed lenses".

It's really a pity that no one tried yet to compare the three high-speed 50'5 (Sonnar, Nokton, Summilux ASPH). Maybe Sean Reid will do it on an M8 🙄
 
horosu said:
You can find it on the right-hand side of Erwin's home page (www.imx.nl), the topic being "development of high-speed lenses".

It's really a pity that no one tried yet to compare the three high-speed 50'5 (Sonnar, Nokton, Summilux ASPH). Maybe Sean Reid will do it on an M8 🙄
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Ah, I see it now. Thanks, Horosu.

I guess that the Sonnar is just too new for anyone to have done such a comparison yet. 😕

Sean has of course already done a comparison of the Nokton with the Summilux ASPH. Maybe if you e-mail him with the suggestion, he'll start working on somethinf for the Sonnar. Now it would be nice if someone would also lend him a sample of the Sonnar. 😉
 
No, that cannot be the reason as Puts has the 21/4.5 C-Biogon in the part 5 report on Leica M8. That lens is not even released yet... 🙄

/Håkan

Huck Finn said:
I guess that the Sonnar is just too new for anyone to have done such a comparison yet. 😕
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While we are waiting for someone to compare the Planar to the Sonnar...

How do you ZM owners find the 1/3 click stops? My Hexanon lenses have 1/2 click stops, so I worry that I might dislike a ZM lens because they are different in this regard?

/Håkan
 
Here's my question, and I'm not sure if it's been addressed yet: how limiting is the 0.9m closest focusing distance on the Sonnar? Is it a non-issue compared to other 50mm lenses 0.7m distance?
 
not a problem here. i hardly ever focus that close.

and i prefer third stops over half stops. i'd get a zeiss if i didn't already have m-hexanons.
 
i also don't normally move in too close so that aspect of the zm lenses is not a concern at all.
as for the 3rd click stops, i normally keep the zi in ae so again, not really a concern.
i use the ae lock for more control.
joe
 
Thanks for your responses. With my 0.7m minimum focus lenses, I find myself running out of focus throw, but maybe I'm trying to use my rangefinder for stuff it wasnt' meant for. Some of those Sonnar images are pretty convincing, to my eye.
 
Nice lens, I like the sonnar a lot. jja, I'm like you, I prefer getting in close and sometimes find even the 0.7 focus distance limiting. It ultimatley becomes a matter of getting used to not doing that with rangefinders.
 
hth said:
While we are waiting for someone to compare the Planar to the Sonnar...

How do you ZM owners find the 1/3 click stops? My Hexanon lenses have 1/2 click stops, so I worry that I might dislike a ZM lens because they are different in this regard?

/Håkan
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On my Voigtlander R2 clone I find that the meter is not sensitive enough to detect the 1/3 stop different. Not sure about Leica and Zeiss Ikon.
 
Hi,

The 1/3 clicks are not a distraction nor are they hard to get used to. I doubt that 1/3 clicks matter much for most negative films (I'm not sure 1/2 clicks matter either). One-third clicks may be more useful for transparency film and digital sensors.

The close focus distance would be a disadvantage if you have no other camera (SLR) or lenses for close-in work. On the other hand, the loss of 0.2 meters is hardly devastating. For me it was a non-issue. Others may prefer to have the option of using that 0.2 meters.

I will be posting ZM Sonnar-C images soon. I do not own the Planar, so comparisons will not be possible.

willie
 
I suspect the 1/3 stop click increments are part of Zeiss's efforts to inform us the gear is higher-precision than other gear. In operation it doesn't really matter to me whether the increment is 1/2 or 1/3 stop, though 1/3 stop seems by comparison a little "fiddly."

The .9m focusing limit for the C-Sonnar is unfortunate; I'd prefer closer and could really use closer focusing. The 50 Skopar goes down to .75m but OTOH the Pentax-L 43mm is limited to .95m 🙂 I have to say it's nice that the Contax-G lenses other than the 90mm focus to .5m...
 
willie_901 said:
The close focus distance would be a disadvantage if you have no other camera (SLR) or lenses for close-in work.
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Excellent point.

On the other hand, the loss of 0.2 meters is hardly devastating. For me it was a non-issue. Others may prefer to have the option of using that 0.2 meters.
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Not devestating, but it is significant to me. It's 8 inches & reduces the minimum focus distance by over 20%. Even if I don't use it, it's just one less thing for me to worry about as I move in closer, making the restrictions of the lens just a little more forgiving. Since I have trouble focusing - no pun intended - on more than one thing at a time, I appreciate that added leeway.

I will be posting ZM Sonnar-C images soon. I do not own the Planar, so comparisons will not be possible.

willie
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I'll look forward to the pictures. Thanks. Every time someone posts it just makes this lens all the more tempting. 😱
 
Dougg said:
The .9m focusing limit for the C-Sonnar is unfortunate; I'd prefer closer and could really use closer focusing. The 50 Skopar goes down to .75m but OTOH the Pentax-L 43mm is limited to .95m 🙂 I have to say it's nice that the Contax-G lenses other than the 90mm focus to .5m...
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I too was disappointed when they came out with this lens with this longer minimum focus distance like CV 50/1.5 Nokton, which is also 0.9.

I think that the Sonnars of 50+ years ago were all designed for this ame minimum focus distance of about a meter, which reinforces my thinking that the intention of the Zeiss/Cosina collaboration on these lenses is to offer classic designs with all their warts.

The minimum focus distance also makes me view this lens as more of a specialty item - just not as versatile & compact as the "slower" Planar except for f/1.5. If you need the speed or if you want that Sonnar look for certain effects, then this is the lens of choice. Especially nice for portraiture & still life IMO. But if you don't need the speed or the fingerprint, you'll probably be better served in most situations by a Planar or Summicron for all around use.
 
I don't think ANY Sonnar focuses as close as a Planar design with the same focal length. Seems to me the Sonnar/Ernostar formulations are very hard to correct at close range, as least without "floating elements."

It's certainly not a coincidence that most close-focusing and macro lenses have the double-Gauss construction. After all, the Planar got its name for a reason. 😛
 
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Here is a discussion on the design problems of the Sonnar--involving close-up and out of focus area character--from the Nikon site that Telenous generously posted earlier in this thread. I've cut and pasted some of the highlights and tried to correct for the idiomatic spherical aberations of the original translation (losing in the process a lot of the original charm):


The Sonnar design, when used in standard high speed (large-diameter) products, offers short barrel length, and imparts less saggital coma flare than Gauss-type lenses. The design method used to reduce aberration, however, is quite complex, making the lenses difficult to manufacture. It also has the characteristic that aberration fluctuation at a close range is large.

A significant aberrational characteristic of this lens is spherical aberration, and as a lens designing technique, a stopper plane--a plane of strong curvature in the rear, three-element cemented lens--is used to correct it. This stopper plane produces a negative high order spherical aberration, and, by this action, excessively occurring flare is cancelled out: "Like cures like".

The manner of the stopper plane correction has a great bearing on the defocus character of the lens. Whether the correction is in "good taste" or "poor taste" depends upon the skill and finesse of the optical designer.

http://www.nikon.co.jp/main/eng/portfolio/about/history/nikkor/n19_e.htm
 
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