Hi I use a AFS 300 and a TC-20E teleconverter on my F5 and have no problems at all. I use these for speedway photography as you will see on my web site. Before I purchased these I confirmed with the local Nikon distributor that they would work together. I also use a Sigma 70-200 2.8 APO HSM lens with a Sigma APO 2X teleconverter. The Nikon one will not fit the sigma lens but the sigma teleconverter fits the AFS300, I do not know if the sigma works on the 300 (haven't tried it yet) Terry James [EMAIL PROTECTED] http://www.wildside.gen.nz
