[mst]

Technically excellent ... but had to go through 4 copies for this review, and none was flawless.



http://www.opticallimits.com/nikon--nikkor-aps-c-lens-tests/625-sigma816f4556dx



Note: clone of the earlier Canon review, if you've read that one, there is nothing new in here for you.



-- Markus

[Albert]

[quote name='mst' timestamp='1305587983' post='8384']

Technically excellent ... but had to go through 4 copies for this review, and none was flawless.

[/quote]



I'd love to pay $200 more for this lens as long as Sigma could do better on their QC... I think Sigma has already built up a quite complete product line supplemented by some unique lenses like this 8-16, and several fast super tele zoom. Maybe it is about the time for Sigma to slow down a little bit on new lens development and spare some time to improve their QC. After all the 200-500/2.8 might be eye catching, but 99% of the users still care more about lenses like 8-16, 24-70, 70-200 and those f1.4 lenses. The QC might be a main concern for a lot of hostile buyers, especially when online shopping are so handy today...

[Yakim]

[quote name='mst' timestamp='1305587983' post='8384']

Technically excellent ... but had to go through 4 copies for this review, and none was flawless.[/quote]



Ouch. That is bad news. For some time (ever since the Canon review) I was considering to replace my 10-22 with this one but this statement scares me. Can you please elaborate?

[mst]

[quote name='Yakim' timestamp='1305611034' post='8390']

Can you please elaborate?

[/quote]



See the "Sample images" section in the review. First three units were decentered, the 4th copy, which was used for the review, was well centered, but suffered from very pronounced backfocus.



-- Markus

[Yakim]

[quote name='mst' timestamp='1305613618' post='8396']

See the "Sample images" section in the review. First three units were decentered, the 4th copy, which was used for the review, was well centered, but suffered from very pronounced backfocus.



-- Markus

[/quote]



Oh my. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/sad.gif' class='bbc_emoticon' alt='' />

[joachim]

[quote name='Yakim' timestamp='1305611034' post='8390']

Ouch. That is bad news. For some time (ever since the Canon review) I was considering to replace my 10-22 with this one but this statement scares me. Can you please elaborate?

[/quote]



Hi Markus and Klaus,



I really appreciate your efforts in trying to come up with a meaningful review. However I am increasingly wondering whether your approach of sending lenses back until you get a good (well above average?) copy is the right approach for Joe Average. Joe might be a bit shy, not fully aware of his consumer rights and be faced with a unhelpful sales guy refusing to exchange the lens. Also if he is a beginner, he might not understand now that his lens is sub-par, but only a year later when he gained some experience. Then it is typically to late to exchange the lens. The problem with these type of issues is, that the lens is not that obviously broken like when the zoom ring is glued into place or the AF gear stripped. This type of thing (decentered optics) can be very hard to argue. I understand that asking for statistical This is most likely spam content on QC is light years beyond what you can deliver on the resource level you have.



For me the bottom line of your review is a severe thumbs down: What ever happens, one just does not buy Sickma. In line with the most famous photozone page from the late 90ies (long discontinued). Klaus knows what I am referring to.

[Klaus]

[quote name='joachim' timestamp='1305632319' post='8405']

Hi Markus and Klaus,



I really appreciate your efforts in trying to come up with a meaningful review. However I am increasingly wondering whether your approach of sending lenses back until you get a good (well above average?) copy is the right approach for Joe Average. Joe might be a bit shy, not fully aware of his consumer rights and be faced with a unhelpful sales guy refusing to exchange the lens. Also if he is a beginner, he might not understand now that his lens is sub-par, but only a year later when he gained some experience. Then it is typically to late to exchange the lens. The problem with these type of issues is, that the lens is not that obviously broken like when the zoom ring is glued into place or the AF gear stripped. This type of thing (decentered optics) can be very hard to argue. I understand that asking for statistical This is most likely spam content on QC is light years beyond what you can deliver on the resource level you have.



For me the bottom line of your review is a severe thumbs down: What ever happens, one just does not buy Sickma. In line with the most famous photozone page from the late 90ies (long discontinued). Klaus knows what I am referring to.

[/quote]



The point is that we don't know the sample variations. We don't reach statistically relevant dimensions. As such it is not possible to withdraw a thumbs up just because of decentered samples. The Canon 24-70 or Zeiss 24-70 are also suckers in terms of QC. Does this mean that Canon and Sony lenses are bad in general ?



If QC was a number one priority we would all shoot Olympus Digital Zuiko ... (4/3, not MFT) ... IMHO.

[miro]

Lens sample variation article [url="http://www.lensrentals.com/blog/2010/03/this-lens-is-soft-and-other-facts"]LensRental[/url]

[joachim]

[quote name='Klaus' timestamp='1305635008' post='8407']

The point is that we don't know the sample variations. We don't reach statistically relevant dimensions. As such it is not possible to withdraw a thumbs up just because of decentered samples. The Canon 24-70 or Zeiss 24-70 are also suckers in terms of QC. Does this mean that Canon and Sony lenses are bad in general ?



If QC was a number one priority we would all shoot Olympus Digital Zuiko ... (4/3, not MFT) ... IMHO.

[/quote]



Hi Klaus,



Thanks for the reply. I hope my original posting made it clear that I completely appreciate the problem you are raising and that I did not ask you to reach statistical relevant dimensions. I wanted to highlight an unease I carry for some time, but have little idea how to resolve. Perhaps averaging all the "rejects" per brand for a year might carry some mileage, but I am not sure.



By the way my DSLR is Olympus <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='' />



J.

[Yakim]

Joachim, Bob Atkins once made a [url="http://www.bobatkins.com/photography/lens_defect_survey.html"]Lens Defect This is most likely spam content[/url]. Have you seen it?