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Thread: UWA Massacre!

  1. #11
    Join Date
    Jun 2009
    Location
    Mount Pleasant, SC
    Posts
    145
    Thanks guys. I think you have managed to make me more confused than I already was. The witty remarks help lighten me up though. I haven't taken the time to "truely" learn this art, and won't really get any better until I try to understand what you guys are saying instead of looking at is as Greek and blowing it off. That and a winning lottery ticket will make me a professional photographer in no time, I am quit sure.
    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

  2. #12
    Join Date
    Feb 2006
    Location
    Des Plaines, IL
    Posts
    9,560

    Unhappy "Oh, it's just a little off ..."

    Quote Originally Posted by Peekayoh View Post
    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.
    I offered an opinion on why Micro-Adjust might be of use, when correcting for a disparity on focus from one end of a zoom lens to its other. Yes, even a substantial temperature change will cause an optic to vary ... okay, that's a great option to use to correct it. I contend that you, the photographer, should not have to use it, if a lens is:
    1. properly aligned,
    2. at a normal operating temperature and
    3. basically not physically warping when you stretch it.


    I have done this enough (way beyond anything I ever anticipated) to know precisely of what I speak. I know when I place a properly aligned lens, fresh off the depot's collimator, the Micro-Adjust is zero ... regardless of the lens. That confirms the α850 is aligned ... kind of the "friend-of-my-friend-is-my-friend" rule. The alignment proves the camera does not have any issue, because it is entirely independent of the calibration of the lens.

    Now, when you get into the Zeiss lens design, it no longer fun to try and align this bad boy. You know, just by looking at this one ... it is going to cost money to play with, because it is truly sealed up.

    Soooooo ... BACK IT GOES! I will not subject the depot guys to even trying to make it work right. This is not third-party glass. This is the "real deal" ... the manufacturer's "best of breed" ... and I expect nothing but perfection from it. If you truly want my coin ... deliver the goods.

    I should not have to align the lens to my α700 ... but, even if I did ... there should be so little difference between it and another α700 that the alignment should transfer without error. The same should go with an α850/900α with the Micro-Adjust @ "+/- 0"

    My a700 has been re-calibrated, anyway, when I had it serviced last year. So, I have to assume it is spot on ... and noting that all the lens focus just fine with it ... what's left to say?

    There is no fallacy here. The real fallacy is believing people will not catch these errors when they seriously inspect their focus test results. I say, "Expect what you inspect."

    I have four OTHER lenses that work quite well on both my FF and APC-S sensors ... and prove to me that the CZ 16-35mm f/2.8 is "misaligned." Nope ... this expensive lens is going back. Fuzzy ain't fixed!
    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

  3. #13
    Join Date
    Feb 2006
    Location
    Des Plaines, IL
    Posts
    9,560

    Lightbulb Focus in question?

    Quote Originally Posted by joenmell View Post
    Thanks guys. I think you have managed to make me more confused than I already was. The witty remarks help lighten me up though. I haven't taken the time to "truely" learn this art, and won't really get any better until I try to understand what you guys are saying instead of looking at is as Greek and blowing it off. That and a winning lottery ticket will make me a professional photographer in no time, I am quit sure.
    @Joe ... you need to try a couple tests with any questionable lens, provided it is a good, wide aperture lens (f/2.8 or wider) and has a minimum focus distance of two-feet or less. (70-300 and 70-200 need not apply)

    One is an angle test. (operate the camera in MANUAL MODE)
    1. Put the camera in "SPOT" focus mode
    2. Open the aperture to f/2 or as wide as you can, then adjust the ISO and Shutter Speed for a good exposure or a slightly lighter one (no more than +1Ev)
    3. Lay a yard stick (or tape measure) on the table ... and put a red line on it at exactly 2-feet.
    4. Take your tripod (do not extend the legs) and place it on the table. Position it so that the center of the camera (about where the sensor is in side it) is hovering right over the end of the yard stick closest to you.
    5. With the DSLR attached to the tripod, look through the camera's viewfinder and tilt-position your focus "centerpoint" to match that red line, exactly.
    6. Autofocus and snap the image ... and then review the shot.


    Ask yourself,


    "Is that red line, 2-feet away, clearly in focus, or is some other graduation of the yard stick in better focus?"


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    Use your computer screen, not the LCD of the DSLR to determine this .. and look close!



    This is only one test, but it can quickly start you on the hunt. If focus looks better somewhere other than the 2-foot mark ...
    hey, don't panic ... YET ... there's plenty of time for that, later. There may actually be a couple of things going on that
    were overlooked:
    1. The M.F.D.(Minimum focus distance - see specs or do this ... *) of your lens is longer than 2-feet!
    2. You may be in "MF" (Manual Focus) ... check to see that all AF defeat positions (AF switch on lens (if applicable),
      AF Mode switch on body, AF toggle switch) are all in their proper position and working. You want the autofocus
      system to be working for this. That is what we are testing.
    3. Your not really using SPOT focus, your camera is in "Wide" or "Local" (w/ the wrong focus point selected -
      you want the center one in this mode)


    If all that is cool, start freaking out. Get another lens from your bag (check the M.F.D. for it. Is the M.F.D. >2-ft? ...
    Yes? Then, get a different lens .. and hurry up about it, we don't have all night) and try the shoot again. If it repeats,
    it may be the camera, itself, could be suspect, and not the lens. If you do get a good looking 2-foot focus ... out of
    the next lens, it's probably time to consider returning that other foul optic. The sooner the better.

    Print these instructions and take them with you. I do hope this helps. Do this with every lens that has an M.F.D.
    less than 2-feet ... just to be sure you are actually getting a solid focus out of it, because you are going to be madder
    than a March Hare if you have been shooting all your images with a misaligned optic.

    EDIT: If you cannot make sense of this test ... try this LINK

    * - Look at your lens. See the measurement (ft/m) in the focus distance window? Rotate the manual focus ring of the lens
    until it is as far from infinity as it will go. Take a reading in that window ... yeah ... some number of feet ... hopefully,
    less than 2. Whatever this number is, on the opposite end of the infinity rotation ... that's the M.F.D.

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    Last edited by DonSchap; 07-30-2010 at 09:22 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
    Join Date
    Nov 2008
    Location
    Monmouthshire, UK
    Posts
    2,152
    Quote Originally Posted by DonSchap View Post
    I offered an opinion on why Micro-Adjust might be of use, when correcting for a disparity on focus from one end of a zoom lens to its other. Yes, even a substantial temperature change will cause an optic to vary ... okay, that's a great option to use to correct it. I contend that you, the photographer, should not have to use it, if a lens is:
    1. properly aligned,
    2. at a normal operating temperature and
    3. basically not physically warping when you stretch it.
    If that sort of disparity exists in a lens, then MicroFocus adjustment will not help and neither will any other sort of adjustment.
    Using the MicroFocus facility affects the lens throughout the zoom range; you can't selectively adjust for each focal length.
    For instance this is from my 70-300mm G throughout much of it's zoom range....
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    You can see that the point of focus remains unchanged from short to long.
    I have done this enough (way beyond anything I ever anticipated) to know precisely of what I speak. I know when I place a properly aligned lens, fresh off the depot's collimator, the Micro-Adjust is zero ... regardless of the lens. That confirms the α850 is aligned ... kind of the "friend-of-my-friend-is-my-friend" rule. The alignment proves the camera does not have any issue, because it is entirely independent of the calibration of the lens.
    I'm sorry Don, it proves nothing and what you are effectively saying is that CaNikon/Sony have expended millions to provide MicroAdjust and it was all for nothing. Really!
    If you have the lens collimated and serviced it will (hopefully) return adjusted to within factory tolerances. In other words not necessarily dead on the optimum.
    The same goes for the camera, the Main Sensor and the AF Sensor will also be within tolerance and not necessarily dead on optimum.
    So put all three together and the performance will inevitably be, "not necessarily dead on optimum" and you can take that to the bank.
    Some combinations of the three elements will be close to optimum and some will be further away from the optimum and it's just pot luck what you get.
    MicroAdjust (if you have it) offers a way of improving the actual peformance.
    Now, when you get into the Zeiss lens design, it no longer fun to try and align this bad boy. You know, just by looking at this one ... it is going to cost money to play with, because it is truly sealed up.

    Soooooo ... BACK IT GOES! I will not subject the depot guys to even trying to make it work right. This is not third-party glass. This is the "real deal" ... the manufacturer's "best of breed" ... and I expect nothing but perfection from it. If you truly want my coin ... deliver the goods.
    Zeiss QC means the lens is checked at every stage and signed off by a highly critical inspector. The chances of a maladjusted Zeiss lens leaving the factory are practically zero.
    I should not have to align the lens to my α700 ... but, even if I did ... there should be so little difference between it and another α700 that the alignment should transfer without error. The same should go with an α850/900α with the Micro-Adjust @ "+/- 0"
    No, this is not the case, for reasons of "tolerances" given above.
    My a700 has been re-calibrated, anyway, when I had it serviced last year. So, I have to assume it is spot on ... and noting that all the lens focus just fine with it ... what's left to say?

    There is no fallacy here. The real fallacy is believing people will not catch these errors when they seriously inspect their focus test results. I say, "Expect what you inspect."
    Again, no, it will be within tolerance and that's not necessarily spot on.
    I have four OTHER lenses that work quite well on both my FF and APC-S sensors ... and prove to me that the CZ 16-35mm f/2.8 is "misaligned." Nope ... this expensive lens is going back. Fuzzy ain't fixed!
    I dare say you do, the same goes for others but it says nothing about the 16-35mm.
    The issues of B/F focus mainly occur when using fast lenses (read expensive) at high magnifications so often go unnoticed.

  5. #15
    Join Date
    Feb 2006
    Location
    Des Plaines, IL
    Posts
    9,560

    Question Where did I go wrong?

    Peter,

    The tests were conducted at a nominal f/5 and for the most part of all lenses, the mutual 20mm. Nothing extreme about it, no matter what the cost.

    Arguably, we can go round and round about this ... but, I can guaranty you one thing ... if it needs a Micro-Adjust, out-of-the-box ...

    GUESS WHAT?

    . . . . . It goes back!
    _____________________________________
    (Feel free to fill in the blank!)

    Micro-Adjust has its place, but I also think these companies are using it to solve their QC issues, when they turn out misaligned glass.
    Rather than take the time and get the lens calibrated, the lazy-populous pop open the little menu on the camera ... and Micro-Adjust the lens
    with a temporary "fix." I have to say, I do not play that way. If it works on everything I have, I am happy ... but, if it does not ... IT WILL!

    ("Warm up the collimator, I'm on the way.")

    Anyway, the massacre is over ... the CZ 16-35mm f/2.8 is gone, removed from my inventory.
    "Enough of this high-priced gla$$ fooli$hne$$," I say!
    Let someone else Micro-Adjust it
    and just be happy ...

    la la la la la
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    Last edited by DonSchap; 07-30-2010 at 07:13 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

  6. #16
    Join Date
    Nov 2008
    Location
    Monmouthshire, UK
    Posts
    2,152
    Makes me wonder why I bothered. Except that, when someone gives out duff information, it needs to be be challenged in case less experienced readers are misled.

    I'm doing my best here to be diplomatic.

  7. #17
    Join Date
    Feb 2006
    Location
    Des Plaines, IL
    Posts
    9,560
    You only have a hand full of Full Frame users to worry about ... the rest are just screwed for LACK of Micro-Adjust. They had to have it corrected or suffer mis-focus ... FOREVER!
    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
    Join Date
    Jun 2009
    Location
    Mount Pleasant, SC
    Posts
    145
    But, no where in her did anyone mention an answer to my original question. Where does one send a lens for repair/calibation? Does it go back to the original manufacturer, or is there a person/group of persons somewhere who are artists at making lenses "see" more better good?
    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

  9. #19
    Join Date
    Feb 2006
    Location
    Des Plaines, IL
    Posts
    9,560
    Well, United Camera and Binocular does most of my third-party stuff, unless it is a warranty repair, then it goes back to the manufacturer for the work. United takes care of that ... I figure it saves me the shipping. They fix it right the first time or ... (see guaranty of work).
    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

  10. #20
    Join Date
    Nov 2008
    Location
    Monmouthshire, UK
    Posts
    2,152
    Joe, chances are your lenses are OK but you can easy check.
    In good light, to minimise DOF, set the widest aperture you can and stand as close as you can, again to minimise DOF. This is best done on a tripod but in good light with a high shutter speed it will be good enough to tell you if you have a problem.

    MFD = 75" Minolta Maxxum 100-200 F.4
    MFD = 15" Sony DT18-70 F3.5-5.6 (Kit Lens)
    MFD = 18" Minolta Maxxum 50 1:1.7(22) Prime
    MFD = ??? Quantaray D28-90 1:3.5-5.6 Ver 5
    MFD = 37" Tamron DiII 55-200 1:4.5-6

    Let the lens AF on the subject and take a pic.
    Now MF on the subject and take a pic.
    Compare the two pics and if the MF one is sharper, you're in trouble.

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