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Thread: UWA Massacre!

  1. #1
    Join Date
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    Unhappy UWA Massacre!

    Okay ... things got a little nuts this month, as they occasionally do.

    It started off where I wanted to improve my KM AF17-35mm f/2.8-4 "D" UWA Zoom lens with something a bit wider and more refined, so at the beginning of June, I obtained the SIGMA AF 12-24mm f/4-5.6 DG EX ... which with that extra 4mm of focal length provides a 122-degree FOV. Just breath-taking. Obviously, this lens is a little dark ... and requires a decent source to get your shot. It shoots sharp enough to deliver the goods without much of a fight. Designed back in 2004, if was a first of its kind UWA and took quite a few awards.

    Then, many pine for the SONY CZ 16-35mm f/2.8, which was released last year (Feb 2009) and seemed to take forever to show up on the shelves. This lens, with its f/2.8 base aperture offers an INDOOR UWA shot, that is hard to imagine unless you witness the difference. It alleviates the use of a power flash and you can render with ambient lighting. All electric focusing drive, it is also the quietest and fastest UWA lens I have ever seen. You literally have to either watch it focus or be touching it to feel the inertia of the elements. That is impressive silence.

    So, I find it for a most excellent price ... at the end of July. Here I sit, with, perhaps, two of the best UWA lenses ever designed. Unfortunately, the Zeiss is not right. It is back focusing. Something I have seen on other Minolta and SIGMA UWA lenses ... but not a Zeiss. I mean the retail price of a Zeiss lens is based on purchasing that silly logo, which is suppose to imply quality testing and performance. Not so fast!

    With the α850's Micro-Adjust, I was able to correct the focus with a "-4" setting. Unfortunately, you cannot do that with an α700. You are just backfocusing. So, despite what some people have said, you have to have your lenses corrected for use on APS-C sensors ... or it matters not what they cost, you are just shooting crap.

    Anyway, SONY is getting this faulty powerhouse lens back ... and, hopefully, it can be corrected with a warranty repair. I have looked and looked, and by the way this puppy is designed, there should be no way a user could make the lens foul up when focusing. It is all internal, behind a weather-resistant design.

    Oh, it's a Zeiss ... yeah, right. OOTB ... meaningless tripe.
    Last edited by DonSchap; 07-29-2010 at 04:37 PM.
    Don Schap - BFA, Digital Photography
    A Photographer Is Forever
    Look, I did not create the optical laws of the Universe ... I simply learned to deal with them.
    Remember: It is usually the GLASS, not the camera (except for moving to Full Frame), that gives you the most improvement in your photography.

    flickr & Sdi

  2. #2
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    Quote Originally Posted by DonSchap View Post
    Here I sit, with, perhaps, two of the best UWA lenses ever designed.
    not sure how you arrived at that silly conclusion; but anyway...i find it VERY hard to believe that every single lens you purchase has a fault in it that requires repair.
    D800e l V3 l AW1 l 16-35 l 35 l 50 l 85 l 105 l EM1 l 7.5 l 12-40 l 14 l 17 l 25 l 45 l 60 l 75
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  3. #3
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    Thumbs down Oh, the unfairness of it all ..

    Rooz ...

    I have no idea how much of this is going on, but I have caught more than my fair share of it. As you are FULLY aware, more than anyone else on the board, my gear is constantly under review and I keep a tight ship.

    I know exactly what I am looking for (of course, when a completely DEAD lens shows up ... that's kind of hard to miss ) ... and I do testing IMMEDIATELY out-of-the-box (OOTB).

    Name:  cz16-35-box.jpg
Views: 139
Size:  235.6 KB

    Occasionally these bad boys really are ... bad boys.

    I am disappointed and not sure how other people (QC and builders/assemblers) miss these rather simple optical tests, because I can take the lens right over to the local depot and they, of course, confirm the misalignment with their device and it gets tweaked or whatever... and from then on, it is fine. Having to do this, every other time, is just wrong.

    My "second" 70-400 was fine OOTB ... and I expect it to stay that way. Yes, when I mounted it, it came right to life! Hooray for a second lens! Excuse me, but I believe the first purchase should have been the completed one. Who knew? Such zany expectations.

    This Zeiss 16-35mm f/2,8 is a "second-hand" lens, but I can assure you it looks brand new and is known to have gotten very little use. Certainly nothing to cause this kind of a focusing error. The entire lens, by design, cannot be interfered with. It is totally protected. You might say it is the closest thing to "idjit-proof" that they make. All this means is that some unfortunate buyer got a screwed-up lens BEFORE I got it. I just found the screw-up! It was always there. C'mon, man ... it's a Zeiss!

    So, regardless of whether you believe I am in a mine-field of screwed up glass ... the proof is in the reality of the situation. No matter how expensive the lens is ... it just does not matter if the manufacturer is not attentive to the quality-control. Someone is going to get this crap.

    Some people just buy the lens, never critically look at the calibration or correction measurements ... then spend the rest of the year complaining that they cannot achieve a sharp image. WELL, NO KIDDING! If the lens is focusing three-inches behind your center of focus (CoF) ... incorrectly assuming it has a good autofocus, you never will, unless you actually mis-focus!

    That simple lack of understanding is precisely what these manufacturers are counting on and allows them to keep pumping out substandard devices.

    Anytime you have to correct a lens, across the focal range, something is WRONG, WRONG, WRONG. Do not allow them to sell you gear that is misaligned like this.

    I say, "KEEP "EM HONEST!" Send them their "gift" right back for repair or calibration! You have an expectation that has not been fulfilled ---> It should work properly!

    Oh, don't get me wound up ...
    Last edited by DonSchap; 07-29-2010 at 09:20 PM.
    Don Schap - BFA, Digital Photography
    A Photographer Is Forever
    Look, I did not create the optical laws of the Universe ... I simply learned to deal with them.
    Remember: It is usually the GLASS, not the camera (except for moving to Full Frame), that gives you the most improvement in your photography.

    flickr & Sdi

  4. #4
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    i believe though, (correct me if im wrong), that the sony zeiss product is zeiss designed but sony made in japan. so i dont think this is a reflection on zeiss' quality control or manufacturing processes.
    D800e l V3 l AW1 l 16-35 l 35 l 50 l 85 l 105 l EM1 l 7.5 l 12-40 l 14 l 17 l 25 l 45 l 60 l 75
    flickr

  5. #5
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    So..... Don (and all) since I don't have the educated/calibrated eye's that you guys have, How do I know if I really suck at this, or it's a problem with the lens? Also, if there is a problem with the lens, who can repair/calibrate them to be properly aligned? Do they have to go back to the manufacturere who built them, or is there a second party that does them with some degree of assurance that it will be "spot on"? With the exception of my "kit lens" all of my lenses are second hand and I have no proof positive that they are quality lenses. It is more of a financial issue than anything truthfully. You probably remember all of the jabber a while back when I was totally clueless about Sony. Thanks in advance for all the advice that I have and will receive from this forum
    Joe Holmes
    Sony α550
    Sony HVL-F42AM Flash
    Sony DT18-55 F3.5-5.6 (Kit Lens)
    Minolta Maxxum 50 1:1.7(22) Prime
    Minolta 35-70 F4 (Mini Beercan)
    Minolta 70-210 F4 (Beercan)
    Minolta 28-135 F4-4.5 (This beast is pretty heavy)
    Minolta Maxxum 100-200 F4.5
    Quantaray D28-90 1:3.5-5.6 Ver 5
    Tamron DiII 55-200 1:4.5-6

  6. #6
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    Quote Originally Posted by DonSchap View Post
    .................With the α850's Micro-Adjust, I was able to correct the focus with a "-4" setting. Unfortunately, you cannot do that with an α700. You are just backfocusing. So, despite what some people have said, you have to have your lenses corrected for use on APS-C sensors ... or it matters not what they cost, you are just shooting crap.

    Anyway, SONY is getting this faulty powerhouse lens back ... and, hopefully, it can be corrected with a warranty repair. I have looked and looked, and by the way this puppy is designed, there should be no way a user could make the lens foul up when focusing. It is all internal, behind a weather-resistant design.

    Oh, it's a Zeiss ... yeah, right. OOTB ... meaningless tripe.
    Oh no! We're back to that issue again, we've thrashed through this before (back/front focus).

    Before we get into that again, though, I'm pleased to see you spending your cash on great glass. With your budget I'd never buy anything but. I also acquired a 16-35ZA along with an A900, I virtually stole it from a guy with more money than sense, so I don't have any qualms about it. He had a Ferrari, a trophy wife and had bought a complete A900 system; he then found his wife was taking better pics with a P&S than he was so, rather than learn how to use the camera, he opted to get rid.

    Anyway, the back/front focus issue.

    I've said it before but this is not a lens problem and sending it back will do no good unless you send the camera with it and calibrate the two together. Of course that may well give you problems with your other lenses.

    The AF system uses Phase Difference to calculate how far (and in which direction) the focus motor needs to go move in order to attain correct focus. System inaccuracies and manufacturing tolerance all add up to defeat the objective of pinpoint accuracy. Normally DOF is sufficient to mean that the result is good enough but fast lenses render any problems more obvious.

    Think of it this way, if you manually focus a lens, it will always be spot on unless 1) your vision is impaired or 2) the focus ring is sloppy or has a very short travel. Your eyes are the AF sensor and your fingers are the drive train.
    Item 1) we can deal with by giving you spectacles or by adjusting the AF sensor.
    Item 2) we can't do much about. The lens can be checked to see that it's within manufacturing tolerances and correctly collimated but that does little to address the problem.

    Without a Micro Adjust function, the only thing to do is adjust the AF Sensor to an average setting across all your lenses. Good luck with that one. Maybe the MA function will be incorporated into the A7xx when it comes.

    What could be nice is an AF system that uses Phase Detect for the initial fast movement and then uses Contrast Detect for fine adjustment. In the meantime, without the Micro Adjust function, you are stuck.

  7. #7
    Join Date
    Mar 2009
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    Perhaps they just send the bum lenses to Illinois!!!
    Darin Wessel
    α 900
    Zooms: Tamron SP AF70-200mm f2.8 Di LD Macro; Sigma 28-90mm D macro, Konica-Minolta 18-70 f3.5-5.6
    Primes: Minolta 28mm f2.8; Sony 50mm f1.4
    Minolta RC-1000 remote commander

    Film:
    Calumet Cambo CC400 4x5 View Camera
    YashikaMat 6x6 TLR (other accessories)
    Minolta Maxxum 7000 w/ Minolta 35-80mm f/4-5.6 & Minolta 2800 flash
    Minolta Maxxum 5000i & Vivitar 728 AFM flash
    What's next???

  8. #8
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    Cool Afaiac

    As far as I am concerned ...

    when I place a lens on the α850, it had better read dead on "+/- 0" or there is a problem with it. Most of the lenses I mount, prime or otherwise, require NO CORRECTION.

    Gosh Don, what does that mean?

    Well, what that means is that with a 'standard' lens mounted ... that is calibrated and aligned properly ... my DSLR's sensor is at the "correct distance" from the back of the rear element. It should, like on every other DSLR that is correctly aligned, require NO adjustment.

    Yes, there may be the occasional goofy alignment or someone bumped the lens. I can allow that, but out-of-the-box ... NO WAY! "+/- 0" is the only acceptable adjustment setting or someone messed up. Now, I admit ... with extreme zooms, having the luxury of tuning can be of real benefit (if you take the time to do this kind of tuning. Some folks are real "anal" about their imaging. Sorry ... everyone marches to a different drum, these days.) as you can set for one end, if it is off-focus and then toggle the Micro-Adjust "ON" & "OFF" to make use of the desired correction. But at the center focal length, it still should be ZERO!

    That's where I am on this Zeiss contraption. It is WAY OFF in my estimation, at 20mm and although, thankfully, the α850 could cope with it ... my other cameras can not.

    I am giving back to the original owner to have it negotiated for repair ... and a "good price" evaporates. It would have been nice if it had worked, but not this time. I'll plow along with the SIGMA 12-24 ... as the comparison showed it does turn out excellent results, I just may need a little more light.
    Last edited by DonSchap; 07-30-2010 at 09:18 AM.
    Don Schap - BFA, Digital Photography
    A Photographer Is Forever
    Look, I did not create the optical laws of the Universe ... I simply learned to deal with them.
    Remember: It is usually the GLASS, not the camera (except for moving to Full Frame), that gives you the most improvement in your photography.

    flickr & Sdi

  9. #9
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    Quote Originally Posted by joenmell View Post
    So..... Don (and all) since I don't have the educated/calibrated eye's that you guys have, How do I know if I really suck at this, or it's a problem with the lens? Also, if there is a problem with the lens, who can repair/calibrate them to be properly aligned? Do they have to go back to the manufacturere who built them, or is there a second party that does them with some degree of assurance that it will be "spot on"? With the exception of my "kit lens" all of my lenses are second hand and I have no proof positive that they are quality lenses. It is more of a financial issue than anything truthfully. You probably remember all of the jabber a while back when I was totally clueless about Sony. Thanks in advance for all the advice that I have and will receive from this forum
    Joenmell you test the camera/lens combination and see what gives.
    Here is a previous thread where the method of measuring back/front focus were discussed.

    Here is a test pic of my ZA.
    In the top set at f2.8 you can see that battery No2 (left to right) is in better focus than No4. Indicating that the actual focus point is a tad behind No3 (intended focus).
    I included the bottom set at f11 to show that stopping down tells you nothing because DOF hides any inaccuracy.
    As I said in the previous post, B/F issues are largely confined to fast lenses.
    Name:  16-35ZA Focus Test.jpg
Views: 123
Size:  750.4 KB

    BTW, congrats on the new lens, it's a good one.

  10. #10
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    Quote Originally Posted by DonSchap View Post
    As far as I am concerned ...

    when I place a lens on the α850, it had better read dead on "+/- 0" or there is a problem with it. Most of the lenses I mount, prime or otherwise, require NO CORRECTION.

    Gosh Don, what does that mean?

    Well, what that means is that with a 'standard' lens mounted ... that is calibrated and aligned properly ... my DSLR's sensor is at the "correct distance" from the back of the rear element. It should, like on every other DSLR that is correctly aligned, require NO adjustment.
    Which is why you end up rejecting most of your lenses until you get one where the manufacturing tolerances cancel out.
    Yes, there may be the occasional goofy alignment or someone bumped the lens. I can allow that, but out-of-the-box ... NO WAY! "+/- 0" is the only acceptable adjustment setting or someone messed up. Now, I admit ... with extreme zooms, having the luxury of tuning can be of real benefit (if you take the time to do this kind of tuning. Some folks are real "anal" about their imaging. Sorry ... everyone marches to a different drum, these days.) as you can set for one end, if it is off-focus and then toggle the Micro-Adjust "ON" & "OFF" to make use of the desired correction. But at the center focal length, it still should be ZERO!
    No, if someone bumps the lens it may collect a ding or a scratch but it won't make it B/F focus. If banged hard enough it may not focus at all which is a different thing altogether.
    That's where I am on this Zeiss contraption. It is WAY OFF in my estimation, at 20mm and although, thankfully, the α850 could cope with it ... my other cameras can not.

    I am giving back to the original owner to have it negotiated for repair ... and a "good price" evaporates. It would have been nice if it had worked, but not this time. I'll plow along with the SIGMA 12-24 ... as the comparison showed it does turn out excellent results, I just may need a little more light.
    So pricewise, you've given up on a good deal for reasons based on a fallacy?
    You know, there's a good reason why CaNikon and latterly Sony offer the MicroAdjust facility.

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