Douglas Green , Feb 15, 2004; 05:04 p.m.
I would look for the older Vivitar or Kiron MF lenses, rather than the Sigma. The better Vivitars were actually made by Kiron. The best bargain is the Vivitar 28mm f2.5 in old Nikon mount (which can easily be AI converted) or the Kiron 28mm f2.0 in AI mount.
The problem with an old F-mount non-AI lens is that they won't work on an F301, I don't believe.
I have bought several of the Vivitars 28mm f2.5 lenses for $20-25 US on ebay, for kits that I assembled for others, and the Kiron 28mm f2 AI cost me around $50 US on ebay.