On Sun, 17 Apr 2005, Jostein wrote: > A couple of days ago I experimented with the AF 1.7TC, the autofocus > teleconverter, on the *istD. My Pentax lenses worked fine, but my > Sigma EX 70-200/2.8 did not work well with the TC. On full opening,
<snip> > Anyone else had the same experiences? No, cause I have no Sigmas, but I am lead to believe that Sigma reverse-engineers the Pentax protocols (as opposed to licencing or sth) with known compatibility issues. Reportedly these have been addressed, but your email indicates (to me) that this may not be the case when it comes to the strange beast the AF T/C is. Just a guess, Kostas
