Originally posted by c a sugg OK -- Just received an SF1, for the price of a couple of rolls of slide film. Looks to be in perfect shape -- except for one little problem. The autofocus doesn't work at all with the 28mm Sigma. The aperture control on A seems to work, but to no wider the f4. 50mm "M" lens works as expected. AF works with a DA kit lens, as seemingly, the aperture as well.
Have here been some subtle changes in the mount specs since the 1980s?
Thanks,
Charles
AFAIK, the basics of AF haven't changed. I have an SF1, as well as a Tamron 28-200mm AF zoom. The lens works perfectly on both the SF1 and my K10D.
Check the electrical contacts on both the lens and camera. A pencil eraser works well to clean electrical contacts. Just be careful not to allow the rubbings to fall into the camera.
Please don't be insulted, but are you sure that the SF1 is set to AF mode? There is a slide switch on the side of the lens mount.