Above: From Top to Bottom: DA560, FA250-600, Sigma DC500, FA400.
There is also a A600 as well (the lower one):-
From these PFC posts (in Traditional Chinese):-
http://forum.pentaxfans.net/thread-134670-1-1.html
http://forum.pentaxfans.net/thread-134602-1-1.html
Who said Pentax is not for Birding after all?! ;-)