Hi guys, I want to get started with off camera flash.. I currently have a Nikon D40 camera and SB-600 flash. The D40 does not have wireless capabilities, but the SB-600 can be used as a wireless slave. What is the best option for me? Should I get an SB-800 flash which will wirelessly trigger the SB-600? Or are there other (cheaper) options? I hear a lot about pocket wizards, is that an option considering I already have an SB-600?