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Thread: 35 FE Sonnar - Decentering. Who else?

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    35 FE Sonnar - Decentering. Who else?

    I just got mine and I am really annoyed. It has very obvious decentering (top right corner never gets as sharp and whole right side is weak). This is not pixel peeping, this is downright mushy.

    Who else has had this problem?

    Also, where? In all the samples I have seen with the 35 Sonnar where there is decentering, it always seems to be top right. Is this my imagination? Is it also my imagination that this is frighteningly common with this lens?

    I've never had such problems with Zeiss ZMs. All have been optically as perfect as the designer intended. The lens I have in front of me isn't even close to being centered... which considering the price, is NOT impressive, especially as this lens is the only one readily available!!!

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    Administrator, Instructor Guy Mancuso's Avatar
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    Re: 35 FE Sonnar - Decentering. Who else?

    Mine seems pretty good but I might sell it anyway. I want a Zeiss 35 f2 ZF instead. Just a straight manual focus .
    Photography is all about experimentation and without it you will never learn art.

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    Re: 35 FE Sonnar - Decentering. Who else?

    I was going to get the 35/2.8FE to match my superb 55/1.8FE, but I'm put off by all of the issues raised on various forums. I know we only get to hear the bad stuff on the internet but the plasticy, cheap, mushy, soft, decentred words are quite offputting.

    I have been using my Zeiss ZM Biogon 35/2 to good effect and will just keep using that with the excellent focus peaking until the wides are sorted out.

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    Re: 35 FE Sonnar - Decentering. Who else?

    I have a 35 f:2.0 Biogon, and I could not find a way to make it work on my A7R. I would love to hear how you do it.

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    Re: 35 FE Sonnar - Decentering. Who else?

    I've had two copies of the FE 35 F2.8 - one was soft on the left and one on the right, but they were kinda diagonal de-centerings really. Both returned, awaiting replacement but if the 24-70 is good I will skip the 35mm because I now have a great copy of the F1.8 55mm and that can be my go-to for perfect.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Sure hope you can return it. You should do so immediately if you can. My copy has very slight softening on the left hand side but it is still the best 35mm I own. That being said I have yet to find ANY 35mm focal length lens that I would call excellent. Wides for 35's all seem to be a crap shoot.

    Victor

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by philber View Post
    I have a 35 f:2.0 Biogon, and I could not find a way to make it work on my A7R. I would love to hear how you do it.
    I have no idea. Point and shoot is my professional approach. I have checked, and rechecked, at F2 - F16 as I was suspicious, but no issues at all - yet. Auto ISO.

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    Administrator, Instructor Guy Mancuso's Avatar
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    Re: 35 FE Sonnar - Decentering. Who else?

    FYI I'm willing to trade someone for a Zeiss 35 f2 in Nikon or even canon mount.
    Photography is all about experimentation and without it you will never learn art.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Mine is going back tomorrow and Sony needs to get their act together. In the UK this is a $1000 lens and my Canon 40mm 2.8 pancake is at least 'straight' on the inside at 1/6th the price. I too was unsettled by the decentering reports, but figured 'what are the chances'. Well, I'm gonna guess that they have a full on production problem rather than a few bad ones. My samples look the same as those I've seen online. Same soft corner/edge!

    FWIW, the build is not an issue for me. The lens is incredibly light, but seems structurally solid and is metal, rather than plastic. The very light weight and perfect balance are good points, but there's no point having the best resolving FF sensor in the world if you cannot put decent lenses on it! AF is fine too. Silent and reasonably quick.

    Regarding excellent 35mm lenses, the CV 35 1.2 II certainly counts. Stunning. I was hoping the little sonnar would be better on the edges and in the corners at wider apertures (as well as much lighter and compact) and it seems it is, at least on the left side....

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    Re: 35 FE Sonnar - Decentering. Who else?

    I'm thinking the same. I was gonna get the 24-70 anyway and will wait to see how that works out before deciding on the 35mm again in a few months. I then have a mind to wait for the Zeiss manual focus lenses at the back end of 2014 if the 24-70 zoom is good and sharp. I can use my canon and M glass in the meantime.

    Think I will wait for clear evidence quality control is 'under control' before playing postal ping pong with lenses. It all smells like rushed production to me.


    Quote Originally Posted by tashley View Post
    I've had two copies of the FE 35 F2.8 - one was soft on the left and one on the right, but they were kinda diagonal de-centerings really. Both returned, awaiting replacement but if the 24-70 is good I will skip the 35mm because I now have a great copy of the F1.8 55mm and that can be my go-to for perfect.

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    Re: 35 FE Sonnar - Decentering. Who else?

    It turns out that Amazon was able to get me a new copy by tomorrow, before I travel, so the refund has been turned into an exchange.

    I will let everyone know how this next copy fares. Fingers crossed.

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    Re: 35 FE Sonnar - Decentering. Who else?

    How long a period do you have at Amazon to return or exchange. I bought mine Dec. 21

    I would even trade mine in for a instant credit.
    Photography is all about experimentation and without it you will never learn art.

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    Re: 35 FE Sonnar - Decentering. Who else?

    you've got 30 days in the UK, Guy.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by turtle View Post
    It turns out that Amazon was able to get me a new copy by tomorrow, before I travel, so the refund has been turned into an exchange.

    I will let everyone know how this next copy fares. Fingers crossed.
    Good luck with your exchange. I haven't observed any decentering with my copy, and wish you the same experience.

    Joe
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    Administrator, Instructor Guy Mancuso's Avatar
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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by turtle View Post
    you've got 30 days in the UK, Guy.
    Looks like I have 30 days here as well.
    Photography is all about experimentation and without it you will never learn art.

    www.guymancusophotography.com

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    Re: 35 FE Sonnar - Decentering. Who else?

    Thanks Joe. I don't enjoy the whole 'setting up experience'. I just want things to work nicely so I can take pictures

    I'm a big fan of paying more for great QC, but I recognise no manufacturer is immune. I've had pretty good luck with Canon (one L lens back in 10 years), Leica has not been immune (two lenses returned, both had major mechanical focus issues) and a clean scorecard with Zeiss. But some of those developed the wobbles! It seems as much a lottery as ever. I have to say though, that all my Leica lenses and Cosina ZMs have been optically perfect and this seems to be a great irritation than mechanical problems, because they can take longer to figure out.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by Guy Mancuso View Post
    Looks like I have 30 days here as well.
    No, I think for purchases made during Xmas season you actually have more than 30 days, at least that's how it was before. I would check with Amazon if it's needed.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Guy, you certainly have 30 days with Amazon.... very easy returns. I'm feeling VERY lucky as my 35mm FE is really quite stellar.... lucky, lucky, lucky..... Been there done that with bad lenses. I have no hesitations returning lenses......

    Victor

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    Re: 35 FE Sonnar - Decentering. Who else?

    Ill have to shoot it more. I have shot very little with it
    Photography is all about experimentation and without it you will never learn art.

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    Re: 35 FE Sonnar - Decentering. Who else?

    I wonder how many of these returned lenses get sent back out to another photographer?

    That's what makes me really nervous about the reports of decentering with these lenses.

    ---Michael
    a7r, a7rII, FE 16-35, FE 24-70GM, FE 70-200, Loxia 21mm, 35mm, 50mm

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    Re: 35 FE Sonnar - Decentering. Who else?

    Even though mine is pretty good I may just sell it immediately and get the Zeiss 35mm F2 which I really liked. My son is bringing me the box and such from home to me here in LA but if someone wants it I can go 725.00 and Ill order a used 35mm F2 from B&H. Its not that I don't want a AF lens its more about having a complete manual kit for the A7r and a AF kit for the A7 which I will just use zooms there.
    Photography is all about experimentation and without it you will never learn art.

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    Re: 35 FE Sonnar - Decentering. Who else?

    I wonder about that too. Do manufacturers toss them out, rebuild them... just repackage them? Same for any manufacturer.

    I'm still astounded by how light it is. It feels like they forgot the glass! If Leica built a lens this light, their chief engineer would add lead to make it feel 'better'

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    35 FE Sonnar - Decentering. Who else?

    Could someone post a few pics depicting the de-centering on your lens?

    Just trying to get an idea of what is setting off the alarm bells.

    Also, I can confirm that the CV 35 1.2 II is superb on my A7r but HEAVY.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by fmueller View Post
    Also, I can confirm that the CV 35 1.2 II is superb on my A7r but HEAVY.
    I purchased the grip to use my 555g ZA 24/2 distagon. The additional camera weight makes heavier lenses so much more pleasurable to use handheld.

    Graham

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    Re: 35 FE Sonnar - Decentering. Who else?

    Sure, these were shot wide open. I have a very handy rug with not only a grid, but good texture. This allowed me to align everything perfectly along the top edge of the frame. I also did the bottom edge, a vertical shot onto the rug and a number of outdoor scenes. All returned the same result: right side slightly softer overall and top right very poor. Its close to acceptable by f8, but....

    The samples do differ in the lighting (not something I could change easily) and have had reasonable sharpening applied. I'll put up with some imperfection if, when sharpened it it not really an issue. Even at 5.6 the difference is obvious and its not a tiny tip of the corner either, but a substantial portion. Looks exactly like the sample someone else posted of a river with wooded banks. The branches were all mushy in the top right at F5.6 and I reckon our two samples have the same error.

    Quote Originally Posted by fmueller View Post
    Could someone post a few pics depicting the de-centering on your lens?

    Just trying to get an idea of what is setting off the alarm bells.

    Also, I can confirm that the CV 35 1.2 II is superb on my A7r but HEAVY.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by GrahamB View Post
    I purchased the grip to use my 555g ZA 24/2 distagon. The additional camera weight makes heavier lenses so much more pleasurable to use handheld.

    Graham
    LOVE this lens on the A7R!

    Although I do not find this lens + EALA4 all that big on the camera, I may give the grip some more thought since I view the A7R as two cameras in one ... kinda like a Puffer fish ... small most of the time, but we can "puff it up" to take the A mounts from 16mm to what-ever mm.

    Thanks!

    - Marc

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by fmueller View Post
    Could someone post a few pics depicting the de-centering on your lens?

    Just trying to get an idea of what is setting off the alarm bells.

    Also, I can confirm that the CV 35 1.2 II is superb on my A7r but HEAVY.
    I checked both the FE55 and FE35 like I do most of my lenses ...

    I subject them to the "Chicken Test"

    An old antique sign we have in the kitchen that I use because it has a round motif I can use to be reasonably sure I'm squared up (circle goes oval or oblong if I'm not fairly flat on and squared up). I also use a round clock face on a Grandfathers clock, and so on.

    BTW, I used a canned profile in LR to fix vignetting and distortion ... while LR4 doesn't have these lenses listed, Irakly and I found the 35 and 50 Ziess ZE profiles do a reasonable job with the FEs when we were testing a dump truck full of lenses we own between the two of us yesterday.

    Both of my FEs did a reasonable job in the corners @ f/2.8 up-close for an apples-to-apples f stop comparison. Obviously f/5.6 is even better.

    A7R, ISO400, 1/100, available light, handheld (even though the light changed a bit, I kept the camera settings the same).

    I'm only showing the FE35 top right corner that seems to be in question ... looked okay to me on my 30" screen at 100%. The other 3 corners were also fine. FE55 did fine ... all 4 corners shown below.

    Also discovered the Leica M 21/1.4 ASPH does vignette (as one would expect from a lens this wide, but does not exhibit color shifts or multi color vignetting like other WAs Irakly and I tested ... easy fix in post. Have to test that lens for corner acuity yet. Same for my M 35/1.4ASPH.

    Most of Irakly's Zeiss WAs failed, as did my M28/2ASPH. But I'll leave that to him to determine as he took all the files with him to play with more.


    PICs: For reference, the sign is 11.5" wide and the circle is 10" in diameter ... so these are close shots which I think is a bit of an acid test. Unfortunately, I'm the only one that has the actual sign to compare to a print ... but both lenses are reasonably accurate right out to the edges. Good copies for what I do.

    The Chicken proves I'm a Lucky Duck I guess But I'm sure someone will disagree and find some fault some where in all this ...

    - Marc
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    Re: 35 FE Sonnar - Decentering. Who else?

    Lets face it, many lenses are a touch decentered, but its a question of whether its within your tolerances. The fact that my just arrived 28-70 Sony kit lens is better in the top right corner on the A7 than the 35 Sonnar is on the A7R says it all, however.

    If I had to be absolutely hair splitting, there is something imperfect about my 5D III and 24-70 L II combo, but the issue is so trivial and performance overall still so spectacular that you'd have to be mad to care. It still shames all but my Leica primes and gives some of the symmetrical Leica wide angle designs a spanking at the wider apertures. Its going to be very interesting to put this lens on the A7R because it clearly outresolves my 5D III.

    Walking around the 'Wildlife Photographer of the Year' exhibition at the Natural History museum in London, there were a few landscapey shot that showed some decentering, with one quite glaring example. The shot was still stunning, however, I did wonder if the photographer had noticed one corner was obviously very soft.

    C'mon Mr Courier, bring me my replacement 35 Sonnar!

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    Re: 35 FE Sonnar - Decentering. Who else?

    Update: The second 35 Sonnar is spot on. Thank goodness. As a 35mm fan, this lens will get a lot of use.

    I forget who it was that posted online somewhere that this lens is 'complicated' in terms of curvature at various distances and he's not wrong. That was very evident from this last batch of testing, but aside from the considerably CA, its a cracker. 120g too... made for travel.

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    Re: 35 FE Sonnar - Decentering. Who else?

    I gave mine the brick wall test and found that at 100% magnification, the files show it to be the least bit OOF in the upper right corner, but so slight that I consider it a keeper. I've tested a number of other 35s (Lux FLE, pre-A Lux, Cron v4, CV 1.2, and 40 Cron) the same way, and it's the best for its match of resolution, absence of corner smearing, and zero color vignetting. Some of theother prime lenses are about the same, and I remember my Canon 24-105 was much, much worse in all four corners. So I have about 98% of the advantages of a prime.

    As to rendering, the FE is very sharp, very contrasty, very useful, and what I'd call 'modern-style boring.' To my eyes the 40 Cron and even the pre-A Lux offer a more attractive rendering, and are sharp enough especially when stopped down to 2.8: almost as good in the corners, lower contrast, and a kind of roundness-of-forms, in contrast to the pores-and-nosehairs detail of newer lenses. But these are just subjective preferences. I value the 35 FE for the times I want autofocus.

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    Senior Member Arne Hvaring's Avatar
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    Re: 35 FE Sonnar - Decentering. Who else?

    FWIW my copy has excellent sharpness and minimal CA over most of the field, but the left hand side of the image (some 15% of the whole) has distinctly poorer sharpness than the rest. Here one sees double contours at wide apertures, but it cleans up reasonably well at f 5,6-8. Sony will send me a second copy as soon as they become available. If the new sample is better, fine, if not I can (just) live with the present lens because of its quality overall.

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    Re: 35 FE Sonnar - Decentering. Who else?

    The 35 FE is clinically sharp. Just use the loupe to wander around the window frame in this image.
    Carl
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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by turtle View Post
    Update: The second 35 Sonnar is spot on. Thank goodness. As a 35mm fan, this lens will get a lot of use.

    I forget who it was that posted online somewhere that this lens is 'complicated' in terms of curvature at various distances and he's not wrong. That was very evident from this last batch of testing, but aside from the considerably CA, its a cracker. 120g too... made for travel.
    I plead guilty. The trick is to focus deep.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by tashley View Post
    I plead guilty. The trick is to focus deep.
    Could you elaborate a bit? What do you mean by "focus deep"?

    //Juha


    Sent from my iPad using Tapatalk HD

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    Re: 35 FE Sonnar - Decentering. Who else?

    In truth, a long answer is required but the short version is that the field of focus seems shaped a bit like an opened umbrella held out directly in front of you, and that if you focus deep into the scene, the umbrella is pushed further forward so that the edges are in focus.
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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by tashley View Post
    In truth, a long answer is required but the short version is that the field of focus seems shaped a bit like an opened umbrella held out directly in front of you, and that if you focus deep into the scene, the umbrella is pushed further forward so that the edges are in focus.
    Tim, I'm trying to get a visual on what your described. There is one medium format 35mm lens in particular I reviewed where the lens has a substantial amount of field curvature to that when one focuses deep in the center of the frame, such as at infinity (as you suggested), the edges sides are soft at infinity but the edges sides at closer range are very sharp. This is analogous to the umbrella shape you mentioned. I'm trying to understand what you mean by the umbrella is pushed further forward, the edges are in focus. Do you mean the edges at infinity are in focus or the edges at a closer range than infinity?

    Thanks for clarification.

    Dave (D&A)

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    Re: 35 FE Sonnar - Decentering. Who else?

    Dave, I can't be much clearer without writing an epic but I will try: imagine that you are facing a 1cm thick curtain of water, an exactly flat, perfect waterfall. You point your open umbrella at it and move slowly forward until the ferrule pierces the curtain. Only that spot of piercing is 'in focus'. Now edge forwards. An increasingly large circumference of the umbrella pierces the water until, optimally, the largest circumference the brolly has to offer is parallel to the waterfall. Now, left to right and top to bottom are 'in focus' and, were the umbrella a fancy pyramidal design with a square base, so would the corners be.

    There will be a whole range of distances between you and the water at which some or much of the central area of this image circle would be in focus, but to get all of it in focus you'd have to 'focus deep' by thrusting your umbrella a long way forward.

    Massive simplification of course. I wrote a piece with Roger Cicala on field curvature and how to focus a tricky lens and it has diagrams and much more detail but forum rules prevent me posting a link to it.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Hi Tim,

    "ferrule", "brolly", all those English words are confusing for someone who barely understands "American"

    OK, your explanation is concise and clear. It's similar to what I've experienced in a select number of lenses, especially wides, that exhibit fairly hefty field curvature. The one aspect of your description that I still have a bit of difficulty understanding, is if you first focus on a point centrally located on that flat field waterfall, I presumed it's already at infinity, so how can you focus any deeper...unless the lens being used is collimated such that it can focus past infinity.

    If you example represents focusing on a flat field waterfall that is closer than infinity, then if one focuses deeper than the waterfall, then the sides and edges of the flat field of a lens exhibiting field curvature, will start to come into focus (depending how deep you focus and the f-stop being used. I think what might have confused me in your original posting is when you said "focus deeper" but I assumed the subject was already at infinity.

    I have a medium format wide angle lens that is a classic representative of this field and curvature principal and its easy to demonstrate by the principals you outlined.

    Next time try writing an epic.

    Dave (D&A)

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by tashley View Post
    ...but to get all of it in focus you'd have to 'focus deep' by thrusting your umbrella a long way forward.
    Tim,

    Not sure I can thrust this well but, are you not at risk of having the centre back-focussed when you "focus deep" to get the edges sharp? I always thought this was one of those compromises we had to make on corner vs. centre sharpness given a particular lens.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quote Originally Posted by jagsiva View Post
    Tim,

    Not sure I can thrust this well but, are you not at risk of having the centre back-focussed when you "focus deep" to get the edges sharp? I always thought this was one of those compromises we had to make on corner vs. centre sharpness given a particular lens.
    Although this question was for Tim...if I could take a stab (with the ferrule of course) at the answer....(like one jabs with the point of an umbrella or as Tim like to say "brolly" ), the center with a wide angle is sufficiently at distance so hopefully focusing deep will keep the center somewhat in the zone of focus (or depth of field). Correct me if I am wrong please.

    Dave (D&A)

  41. #41
    Subscriber Member tashley's Avatar
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    Re: 35 FE Sonnar - Decentering. Who else?

    Dave, you are correct. Of course, with longer lenses you win in that filed curvature becomes less of an issue and you lose in that you have less DOF but my general practice with these sorts of lenses is, for a planar subject at some distance, to stop down to F5.6 or tighter and then focus as far into the scene on centre as I can get away with. Higher resolution sensors make it more difficult. The Nikkor F1.8 28mm G lens is a classic of this sort but is great for shooting cone-shaped subjects such as an alley of trees receding into the vanishing point...

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    Re: 35 FE Sonnar - Decentering. Who else?

    Quite agree Tim! Slight telephotos bring on their own set of issues where field curvature is concerned but I was restricting my comments mainly to wide-ultra wide angle lenses.

    Although I'm familar with the issues of the Nikon 28mm f1.8G, the lens that I encountered to be notorious for displaying fairly extensive curvature was the medium format 35mm lens I mentioned previously. The curvature becomes more extreme at greater camera to subject distances and it's not until around f11 at mid distance subjects that the depth of field becomes significantly large enough to achieve good sharpness across the frame At subject-focusing distances close to infinity, even f16 leaves some residual evidence of the curvature and it's hard to achieve uniformity of sharpness across the frame of a field subject.

    Of course as you pointed out, it can work in the photographers favor for cone shaped subjects. I was photographing a semi-circle reflecting pool (umbrella shaped) that was tree lines around it's perimeter. Even at f4.5, the entire semi circle of trees was sharp, edge to edge, which wouldn't have been possible if the trees were in a line, straight across.

    It's well known in optical design that in wide and especially ultra wise angle lenses, especially those designed at a reasonable price point, that to increase sharpness in performance, curvature and distortion is the price one pays. Look at the 3rd party 14mm f1.2 lens (sold under various labels)....very sharp lens with tons of barrel distortion. Same goes for the quite good sharpness of the Nikon 16-35mm Vr lens at 16mm. They achieved good sharpness at the wide end by allowing distortion remain as part of the optical designed. There are many other examples that could be cited.

    Dave (D&A)

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    Re: 35 FE Sonnar - Decentering. Who else?

    Thank you gentlemen.

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    Re: 35 FE Sonnar - Decentering. Who else?

    Hi!

    I am currently evaluating my newly purchased Sony FE35 and FE55. I am very new to lens testing, but I would like to be sure that my new lenses is acceptable and working good.

    I have included a set of photos taken of my computer screen following this method from Photozone.

    Photozone - Do-it-yourself centering sanity check - Lenses -

    There are two crops each of two photos, manually focused in the center, sorry for the bad light. The first picture is from the FE35 and the second is from FE55.

    What do you guys think of the result? Is the decentering level acceptable?

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