Mr Chan posted, among other things: As a result, problems could range from metering to AF. > Most of the problems I have read are related to Canon EOS & Nikon AF > systems. I do not know if Pentax is on the list, but should be aware of.
The only Sigma lens I ever owned was an autofocus zoom and it wasn't fully compatible with my Super Program (it would report an incorrect aperture). There was a person who posted frequently on rec.photo.equipment.35mm who reported the same kind of error with a different Sigma zoom on a Super Program. So it would appear that Sigmas did have compatibility issues with Pentax also. I still have the pieces of that Sigma zoom -- it fell apart one day while in use -- I don't plan on buying any more Sigma lenses.
