This user experienced an obvious FF issue with his DA 21 Limited lens and conducted a series of simple but yet effective test to confirm the problem:-http://forums.dpreview.com/forums/read.asp?forum=1036&message=20984715In contrast, another two different users experienced BF issue with their each own copy of the DA 21 Limited lens:-http://forums.dpreview.com/forums/read.asp?forum=1036&message=
