C Sonnar

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TJV

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Hello all.
I've only ever heard people talking about focus shift in the ZM C Sonnar at 1m distances when focusing on test charts or rulers. If you have an f2.8 calibrated version, how much will it front focus at 2m when at f1.5? Obviously the depth of field will increase as the film to subject distances gets longer, but at what distance does the intended focus point get overlapped by the actual focus' depth of field?
I'm really considering one of these lenses and am trying to figure out how much I'd even notice the focus shift in real life.
 
maybe ou can try to buy some russian jupiter and see how much focus shift bother you. im using jupiter 8 for years and i never had problems with shift in real life...
 
If you buy the lens just forget you ever read about the focusshift and use the lens in practise (not for ruler and brickwall tests!!!). You soon will find out the issue is blown out of proportions.
Thinking about it all the time and planning corrections in advance will drive you nuts and would make he lens unusable for day to day use .
In the end your number of hits and misses focussing the lens is important ...... my percentage hits with this lens is not significant lower than with a lux asph or a noctilux.... so i consider the focusshift irrelevant for MY type of use (pictures of people) . I never formaly tested my lens for focusshift and can't say from day to day use if the lens is optimised for 1.5 or 2.8, and frankly do not care about it.
 
I suspect that unless I'm being very critical I wouldn't notice it either. Zeiss lenses in ZM mount aren't stocked here in NZ so I can't see one in person. I just checked the DOF calculator and it seems that at 2m the depth of field effectively increases by four times but I'm not sure how that relates to something like front focus caused by the Sonnar design. Perhaps the focus shifting really is just an internet hype myth after all.
 
From my experience, it will front focus at least 30cm, and basically the focus never gets completely covered by the depth of field - not even at infinity. What people who never used the C Sonnar don't know, is, that the C Sonnar does at f2.8 a job which no other lens can do: it gives you a very pleasant, sharp and useable dof ( you get about 12 cm of sharp zone at 1.5m, which is the standard portrait distance), but it blurs the foreground and background as if it was an f1.4 lens, they just get dissolved. So the final effect is pretty striking, and it is more evident at f 2.8 than wide open due to higher contrast of the image.
 
mfogiel said:
From my experience, it will front focus at least 30cm, and basically the focus never gets completely covered by the depth of field - not even at infinity. What people who never used the C Sonnar don't know, is, that the C Sonnar does at f2.8 a job which no other lens can do: it gives you a very pleasant, sharp and useable dof ( you get about 12 cm of sharp zone at 1.5m, which is the standard portrait distance), but it blurs the foreground and background as if it was an f1.4 lens, they just get dissolved. So the final effect is pretty striking, and it is more evident at f 2.8 than wide open due to higher contrast of the image.
Click to expand...

Man, 30cm! I didn't expect it to be that much, do you think that's due to possible variances in the RF unit or does the front focus actually increase with more distance to subject? Is that with the f2.8 optimized version? BTW, for general use, is f2.8 the best aperture to have it calibrated to or does f1.5 make more sense? I positive it's a great lens judging by a few samples I've seen floating about the net.

Thanks for taking the time to answer these questions, I know this issue is somewhat of a drag. I just need to be sure about the purchase because I'll have to order one in from overseas and, effectively, wave the option of return.
 
This is an example of what happens with your focus wide open from about 2 meters
675581008_348ba13689_b.jpg

I was focusing on the ear of the dog on the pavement.
Take a look at this
http://www.flickr.com/photos/59177039@N00/sets/72157602216140269/

and at this thread
http://www.rangefinderforum.com/forums/showthread.php?t=51742
and this
http://www.rangefinderforum.com/forums/showthread.php?t=58681
And watch this
http://www.flickr.com/groups/m-mount/pool/tags/ZeissCSonnar50mmf1.5/show/
 
I agree, that's really shocking! Is this consistent with other peoples copies? And judging by Mfogiel's set on flickr, if it's normal behavior, I couldn't live with those sorts of limitations when working within three meters.
 
TJV, you're still not getting the point: if this lens was sold just with the f2.8 fixed aperture, it would still be worth its price tag in *****s. This is the best portrait lens ever made. In fact, I have 2 versions, so that I use one for the f1.5-2.0 range and the other for the f2.8-f16 range. If you want a general purpose 50mm there are lots of other lenses available.
 
mfogiel said:
TJV, you're still not getting the point: if this lens was sold just with the f2.8 fixed aperture, it would still be worth its price tag in *****s. This is the best portrait lens ever made. In fact, I have 2 versions, so that I use one for the f1.5-2.0 range and the other for the f2.8-f16 range. If you want a general purpose 50mm there are lots of other lenses available.
Click to expand...

i've been lusting after this lens for a long while and finally found one used (optimised for 2.8) though i know i'll be shooting wide open as well... the examples on your flickr page were made with this and i'd be quite happy if i could get those results at f/1.5. did you just adjust to shooting it with the focus shift?

i would dearly love to have both options, but i'm afraid that isn't in my budget. i figure the 2.8 is a better all around lens with a special feel that i'm likely to use more often. it still has quite a bit of character in the mid ranges even if it isn't quite as dreamy as when it's fully open.... arghhh!
 
Get one optimized for F1.5 or even better F2.0

I had two when they first came out and yes, they are miserable to focus at full aperture if they are adjusted for F2.8.

My third is optimized for 1.5 and I love it.
 
Dan States said:
Get one optimized for F1.5 or even better F2.0

I had two when they first came out and yes, they are miserable to focus at full aperture if they are adjusted for F2.8.

My third is optimized for 1.5 and I love it.
Click to expand...

how is it at other apertures, though? that's my fear...
 
i just use mine. i don't compensate for anything. i focus on what i want to be sharp and funny it's usually sharp in the photo.
i have some pics from it on flickr, in the farmer's market set, if you care to look.
it's a great lens, especially for someone like me that does not normally shoot much with a 50. it's different enough for me to consider it a specialty lens.
 
back alley said:
i just use mine. i don't compensate for anything. i focus on what i want to be sharp and funny it's usually sharp in the photo.
i have some pics from it on flickr, in the farmer's market set, if you care to look.
it's a great lens, especially for someone like me that does not normally shoot much with a 50. it's different enough for me to consider it a specialty lens.
Click to expand...

is yours 1.5 or 2.8 optimized?
 
mfogiel said:
TJV, you're still not getting the point: if this lens was sold just with the f2.8 fixed aperture, it would still be worth its price tag in *****s. This is the best portrait lens ever made....
Click to expand...

I disagree with this point in general, even though I do like Sonnars and the ZM 50/1,5. I guess it depends on what the criteria are for 'best' portrait lens; is it most unique, or useful for most situations, or most dependable or even most pleasing OOF areas or something like handling or finish, etc... The Nikkor 85/2, the Leica 75/1,4 are examples of lenses that are superb portrait lenses imo; this is not to mention some bloody amazing portrait lenses in LF or MF, but I assume your comment was intended within the borders of 35mm lenses. The ZM 50/1,5 seems to me to be one of the more unique sonnar designs in terms of its rendering; but I would suggest other focal lengths are more functional as portrait lenses per se. Perhaps you meant, 'best 50mm portrait lens ever made'? Even with that, I could see Gabriel MA wanting to make a pitch for the third version summilux.
Respectfully, Thomas
 
Anytime you are considering a Rf lens - go to Flickr and type in the tag for it. there is usually 100's of shots with the lens there. For the 50f1.5 - just ttype in "Zeiss C Sonnar 50mm f1.5" and that will give you plenty of samples.
This said, I have had the 50f1.5 S Sonnar since it came out and I cant really say that I have had problems with focus shift - at least that I can blame the lens for! I find it one of my favourites among the 50's (and I have a lot of 50's!). Very smooth rendition with nice transitions from dark to bright. It is a Sonnar type lens and they usually have a slight shift in focus when you hit f2-2.8, but unless you spend your days shooting brickwalls, testcharts etc, you will never really have a problem with it. I just finished aseries of shots with three different Sonnars, the C Sonnar 50f1.5, the C Sonnar 50f1.5 in SC mount(Nikon Rf camera) and a venerable Sonnar 50f1.5 from my Contax IIa. They all behave similarly - sharp where you need it and nice out of focus rendition.
My advice is to get the lens and shoot. You will most likely never have a problem with it.
If you are looking for "absolutes" when it comes to 50's - The Summilux 50f1.4 Asph is the sharpest, but also the harshest of them (with a huge $tag) - this is followed by the ZM Planar 50f2.0 and I would put the C Sonnar 50f1.5 close to the Planar here. Both are very good and enough difference in the way they render 3 dimensions into 2 that I have one of each!
 
I think some of this depends on how you plan to shoot the lens. I had one optimized for f/2.8. But when using it wide open and up close, I found the focus shift to be less than ideal. Just a personal thing, but I didn't like it.
So I sent mine back to Zeiss to have it adjusted.
I later sold the lens and picked up a 50/1.4 Nikkor ltm to use as my 50. There are times, though, when I think I should have stuck with the ZM sonnar a little longer. It's a neat lens.
 
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