Originally posted by stevereidlrps
not sure about your combo of TC and lens but i use a Pentax 1.7 AF Adaptor with my Tamron 70-200 f2.8 without any problems so it's likely your combo will probably work OK too, but there is probably a member on here that uses your combo and will give you more accurate info
I tried this tonight, and yes, it appears to work!!!!
So that with the K5, we are talking about a 510mm?
So the Tamron - $800 and the 1.7 AF is about $400 - much less than the coming 500+ DA lens and faster!
Nice.