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  1. #11
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    Yeah I will. I'll have to do it at multiple focal lengths too.

  2. #12
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    lol @ this thread.
    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. #13
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    Red face Same old story, different day

    Quote Originally Posted by Peekayoh View Post
    Oh no! Not again!

    Look Don, I'm not saying that your lens is not OOT (out of tolerance), in fact regular QC failures at Tamron and Sigma mean it's quite likely is.
    That doesn't excuse you from claiming that once the lens is adjusted to be within manufacturing tolerance everything in the garden will be lovely.
    Why? Because there is no guarantee that the camera is within tolerances.

    Unless a camera and all it's lenses are calibrated together, chances are there will still be a problem. Even then it's not possible to achieve perfection, just good enough.
    This is why, contrary to your opinion, the camera micro adjust feature is a godsend albeit only available on semi-pro models.

    Taking a hypothetical situation with one camera and one lens and let's say that the design tolerance is +/- 10.
    The camera happens to be at -9 and the lens at +9 so that the two tolerances cancel each other out giving the appearance of a perfectly adjusted combination.
    You get a new Tamron lens which just happens to be spot on at +/- 0, but in combination with this particular camera it will appear to be a maladjusted -9 so you return it.
    Tamron techs have a go at correcting the lens and end up at -5 (well within tolerance) and happily send it back.
    You expectantly stick it on the camera only to find that the lens is now worse than before at -14.
    I leave you to imagine the to-and-fro and the acrimony that follows.

    And it doesn't end there! You may be in the unlikely heaven of having both camera and lens at the sweet spot of +/- 0 but what about discrepancies in the AF system.
    You can set up on a tripod and focus on a target and have a different plane of focus each time. The Phase Detect sensors are surprisingly good but not spot on and the drive train which carries the focus elements into position has it's own tolerances and inaccuracies.

    If that weren't enough, many lenses suffer from a shift in the plane of focus at different distances from the subject. And many Zoom lenses also suffer from a shift in focus during zooming.
    Peter,

    I have to say ... when I get the returned-for-service lenses back, they are SPIT SPOT! With my IT/Manufacturing background, I have been through manufacturing QC before and it is a place where companies cost cut ... and they take "liberties" when they have a clientele that are rather ignorant of what the problem is. Most newbies never suspect a back focus issue with their new lens and hence, it goes for a long time, if ever, from being suspected or corrected.

    I am not buying into the fact that you must send your gear in, all at once, to have an alignment performed. That seems entirely ludicrous, because these lenses should work correctly on my camera, your camera, that guy in Ethiopia's a900, Frank's new a580, Dave's a330 and Andy's a230 .... I mean any of them, if the LENS is correctly aligned. In the camera, the distance to the sensor is supposed to be EXACTLY the same. That is SONY's responsibility to the "QC circle of life."

    I have to tell you, the "battery test" was, perhaps, one of the best quick checks we ever kicked around. It spotted problems before the photographer pulled his hair out wondering, "What in the hell is wrong with this P.O.S. lens?" (<- I have heard these words echoing in rooms I have been in. Weird, huh? Who knew?)

    Anyway, TAMRON will make it good. I have nothing but success with these returns. SIGMA also has done their part. The only manufacturer I have had issues with, believe it or not, has been SONY. My China-made 50mm f/1.4 simply did not work correctly. The aperture would not close down, routinely. It took three returns for them to get it right. So, third-party is my hero, still the annoyance of having to have the lens "revisit" its mother has me madder than spit.
    Last edited by DonSchap; 05-09-2011 at 09:15 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. #14
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    Quote Originally Posted by Rooz View Post
    lol @ this thread.
    You just mixing it up, 'Rooz?' Real helpful.

    Must be a "post count" thing, huh?
    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

  5. #15
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    Dec 2006
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    God's Country - Australia
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    lol sorry mate...ive just never known anyone to have so many issues with their equipment. its uncanny.
    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

  6. #16
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    Yep, the bad ones end up at Don's door, or do they?

    Quote Originally Posted by DonSchap View Post
    I am not buying into the fact that you must send your gear in, all at once, to have an alignment performed. That seems entirely ludicrous, because these lenses should work correctly on my camera, your camera, that guy in Ethiopia's a900, Frank's new a580, Dave's a330 and Andy's a230 .... I mean any of them, if the LENS is correctly aligned. In the camera, the distance to the sensor is supposed to be EXACTLY the same. That is SONY's responsibility to the "QC circle of life."
    Don, in the real world, your perception that the manufacturer can achieve perfection is simply not tenable. It's like the starving Bee crawling towards the honey pot. As it weakens, each passing minute halves the distance between it and the pot. When will he reach the pot? Answer, never.

    It's the same with precision engineering, you can only strive toward perfection and the law of diminishing returns dictates that the more you strive, the harder it gets and the more it costs. So Manufacturers make qualitative decisions. Tamron and Sigma are mainly building down to a price so you get compromised build quality and a cavalier attitude to QC (Quality Control). I suppose they figure that it's cheaper to spend less on QC and deal with returns because most users either simply won't notice a poorly adjusted lens or will just accept it. I'm thinking that the strategy works because people are buying their gear despite the compromises but if every buyer decided to return their lens for adjustment, the Manufacturer would be on a hiding to nothing.

    Zeiss take a different approach and it shows, both in terms of quality and cost.

    At the end of the day, it's up to the Customer to decide which approach suits them best and of course money talks; Caveat Emptor, as they say.

    BTW, I'm not questioning your decision to return the lens, I applaud your tenacity and resolution to have it right. I just think your perception of right is a bit, well wrong.

  7. #17
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    Question Can you really debate the importance of accurate focus

    Quote Originally Posted by Peekayoh View Post
    BTW, I'm not questioning your decision to return the lens, I applaud your tenacity and resolution to have it right. I just think your perception of right is a bit, well wrong.

    Peter, I know from where I speak, so please to be offended when I say, "Are you, like, on something?"

    Historically: I spent ten years in Uncle Sam's Canoe Club (the US Navy), mostly as a calibration technician, where it was my job to make sure everything was within tolerance and read ZERO when it was suppose to. Not "-5" or "+3", but frickin' ZERO! Every piece of test equipment that I cycled through my calibration stations had to be absolutely, without a doubt, dead-on and within tolerance. Otherwise "REJECT!" with a big red tag. Oh, there were levels of in between, but they were clearly stated on a "Special" calibration tag to ALERT & WARN to user of the equipment where the question marks could be. They were not passed through just to get the work done. Too much was relying on this activity and the US Navy spent a lot of money in equipment, time, and training to put it all in force. My appreciation for the National Bureau of Standards is well noted.

    I would suggest that your thinking is far & away too liberal if you would suggest that that you can release a "precision product" into the marketplace that has not been PRECISELY measured. The argument, in this case, stands. The SP AF 60mm f/2.Di MACRO LD (IF) lens is supposed to be a precision device, not some toss-away "kit lens." Every photographer counts on the lens delivering "killer" focus, especially in the realm of MACRO photography. You simply cannot deliver the image with something that is focusing ... well, elsewhere. This is an unreasonable expectation and I am truly surprised that you, of all blokes, would pander to the manufacturer's side. We need to hold them to a standard of quality, not excuse them. A mis-focusing lens looks just like one that gets it right-on-the-money. It is only in the diligent and close operation of that lens that you can tell that something is "****ed up."

    IMO, excusing people or corporations is specifically why we have the problems we do in much of the world. Sloppy work -> Sloppy results. It all cascades downhill. If your tools are defective, then the results are going to less-than-par. Personally, I see that as a real undesirable result. How about YOU?

    I mean, this whole thing sounds like a scene from Star Wars - A New Hope (the original), to me, where, Peter, you are "Ben" and some poor, newbie photographer is the "Trooper", and the need for a precision focus is the "droids":

    EXTERIOR: TATOOINE -- MOS EISLEY -- STREET.

    The speeder is stopped on a crowded street by several
    combat-hardend stormtroopers who look over the two robots. A
    Trooper questions Luke.

    TROOPER: How long have you had these droids?

    LUKE: About three or four seasons.

    BEN: They're for sale if you want them.

    TROOPER: Let me see your identification.

    Luke becomes very nervous as he fumbles to find his ID
    while Ben speaks to the Trooper in a very controlled voice.

    BEN: You don't need to see his identification.

    TROOPER: We don't need to see his identification.

    BEN: These are not the droids your looking for.

    TROOPER: These are not the droids we're looking for.

    BEN: He can go about his business.

    TROOPER: You can go about your business.

    BEN: (to Luke) Move along.

    TROOPER: Move along. Move along.


    I assure you, TAMRON will get their little "manufacturing defect" back, as per the warranty statement, and when it returns, hopefully, that will be the end of that, otherwise, they can buy it back from me and sell it to some other unfortunate photographer.

    I have a list of lenses to watch out for, and now, this one is on it.

    Buyer beware of what is out there. Expect what you inspect.
    Last edited by DonSchap; 05-10-2011 at 01:23 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

  8. #18
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    Nov 2010
    Location
    Apopka, FL
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    447
    I think you are both right to an extent. If they spent more time checking every lens the lens's would cost more money and most likely a lot more. But then they should check at least half of the lens's that they produce not 1/4.

    some of the lens's dont have to be checked as much as the high dollar ones, like the multi use lens's around the 18-250 kinds

  9. #19
    Join Date
    Aug 2009
    Posts
    316
    Here we go again...
    Don, you can't expect cheaper third party lenses to be on par QC-wise. If you want absolute perfection, which is unrealistic, then quit trying to be cheap and pay for it. Buy the Zeiss lenses, etc.
    Like Rooz said, buy right and buy once (not sure that was in this thread).

    Just to be clear: this lens you bought IS NOT a precision product. Sorry, it never will be. Laparoscopic equipment IS(people's lives are at play), and so are the steppers Nikon and Canon make (and they cost millions of $), to give a couple of examples. A lens to take some pictures? NEVER will be. It's just not that important, and you obviously don't want to pay for precision anyway, or you wouldn't be bothering with a Tamron or other cheaper third-party lenses.

  10. #20
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    Feb 2006
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    Des Plaines, IL
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    Red face "Again" is absolutely RIGHT! I don't know ...

    how many times I try to explain this ... someone inevitably misses the point. It is not that the lens in question CANNOT do what I am asking. It can.

    Try and register that FACTOID.

    All I am saying is: "Make it work like it should, BEFORE I buy it."

    One stop shop. It should not be:
    1. buy it,
    2. then recycle it back to service for true alignment,
    3. then go on about your day.


    I mean, how about we cut out the alignment middleman, which costs ME additional money? Is that what the $100 rebate is all about? Having the funds to get the lens back to the manufacturer for alignment?

    A lens has but one mission: get the image to the sensor. That's it. This entire episode revolves around simple precision, but is a definite example of the schlock effort than has crept back into manufacturing, today. We need to ferret it back out, plain and simple.

    I know many of you may not have been around when the Ford Motor Company went through its bout with quality issues. The time was 1980-1982. The cars, horrendous. People were furious with how lousy the builds were and I defy you to find one, to this day. Junk is junk. Well, they got labeled and knew they had to turn it around or lose the market to the imports and GM. They implemented a series of ground-level quality improvements and the slogan "Quality is Job 1" took over. They knew they had issues, identified them and corrected them.

    Well, it seems that the old ways die hard and history repeats itself. I suggest that if you haven't tested your newer lenses for focal accuracy, you do so. It is a simple test ... and worth each picture you snap, from here on in.

    You want better photography? How about we start with making sure our respective gear works properly and at its peak capability? Try something baseline corrections, first. Then, go shoot something and smile.
    Last edited by DonSchap; 05-10-2011 at 03:11 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

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