Hello all! I wonder if anyone out there can help me - I was thinking of buying a Nikon R1C1 Macro Flash Kit for my use with my D80 and Sigma 105mm f/2.8 EX DG macro lens (I'm into insect photography). However, the flash kit comes with a variety of adapter sizes (52, 62, 67, 72 and 77 mm), but the thread on the Sigma is 58mm as far as I know. Does anyone know if it's possible to get a 58mm adapter for this kit? 
