Wondering if anyone has any thoughts or experience with using teleconverters on macro lenses. I have a Tamron 90mm f/2.8 Di for my D70, and would like a little more range. Should/would've gone with the 180mm if finances permitted. I was thinking about the Tamron2x... speaking of which, I see two listed on thier site; the AF version and the SP AF version... the latter being more expensive. ASAIK, the SP stands for SuperPerformance as per Tamron, so I'm assuming either would work but the SP is high quality... no? It would be nice to be able to use it on my Tamron AF70-300 LD aswell... although the effective aperature would be crappy... might be fun for distant tripod exposures.. moon and such maybe? Thanks for your thoughts, once again.