The other day I stumbled upon this lens in some thrift store near where I live. A Sigma 80~200mm f/3.5 ~ f/4 "high speed" zoom, for Pentax. It looked pretty dented, didn't have any lens caps, the front element was dirty and I didn't have my camera with me... however, focus and zoom seemed smooth and the aperture blades seemed responsive enough... also, since it was only 12,50 euros, I couldn't really leave it
I thought it was a pretty interesting lens... it has one ring
to rule them all which you slide forward and backward to zoom and turn to focus. Also, it has a build-in lens hood. It has the same solid feel I love about my Pentax M lenses, although the aperture ring feels just a tad flimsy.
Unfortunately, coming home I found not only the front element was dirty. As you can see in the picture below, there is what looks like dust on the inside as well. I'm not sure if this could be fungus as well? Anyway, it does seem a little soft, especially wide open, and not too contrasty.... Still, I think it's a pretty good bargain for such a fast zoom lens... and it has already proven its worth during a graduation ceremony with poor lighting where I wanted to do some close ups without getting too close myself.