Hi all. I just picked up a few lenses from a local advertisement. The 2 cheapo Pentax's will work with the m42 adapter I already have. The other one I picked up was a Vivitar 1 series 70-210mm with macro ability. He pulled it off a Nikon F10 so my research tells me it is an F mount, but just a quick search on Amazon and ebay and all I could find was a nice Voigtlander for $180. I really just bought this on a whim as a possible macro toy and was hoping there existed an el-cheapo Chinese job for $10...am I missing something?