I have the Sigma 100-300 f4 and their matched 2* APO teleconvertor. This hunts a lot and is very difficult to lock onto moving subjects. I gave up trying to photograph planes at Duxford with this combo. And that was on a bright day. Tripod mounted and with static subjects which make easy AF targets it does fine with. The big question arising from your statement is what were you focussing on?
> -----Original Message----- > From: adphoto [mailto:[EMAIL PROTECTED]] > Sent: 23 January 2003 12:15 > To: pdml > Subject: Does this happen with anyone elses MZ-S plus a question > > > I put my 300mm 4.5 FA zoom and teleplus2x convertor on my > MZ-S and guess what autofocus was fast and very accurate. > Better and faster than my tokina 80-200mm zoom. I then got a > little excited and tried a sigma 400mm macro 5.6 and provided > it was bright sunlight it worked about 50% of the time and > funnily it picked up moving cars better than still objects. I > then used it with my oldI was told by someone that two times > convertors didnot work with lenses with a apetuire size of > less than 2.8. Are the sigma apo 1.4x and 2x convertors good > quality teleconvertors and will they produce good sharp > contrasty images.? > >
