Recently I have seen four user reports by four different owners of the DA 17-70 about the inability of completing AF with the lens in the range of 50 to 70mm, in a Chinese forum. Direct links are as below:-
http://www.dchome.net/viewthread.php?tid=875053
http://www.dchome.net/viewthread.php?tid=875053&page=1#pid10272648
http://www.dchome.net/viewthread.php?tid=871324
http://www.dchome.net/viewthread.php?tid=871324&page=1#pid10221635
(Above: First Three Posts are in Traditional Chinese, the Fourth is in English)
So, what's going on? What happens for those lens units? What causes the problem? Design issue(s)? Quality issue(s)? Or Both??
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