Great lens.. you will love it! Any flash will do... if diffused. I use an SB-900 a lot with one of the small on-flash 6x8 mini softboxes for a lot of my macro work. It helps to have a decent macro flash bracket that will allow you get the flash over the subject. I also like to use a Lastolite 9x9" softbox. If you remember some of the butterfly shots I posted last year, that was when Robin took this shot of me with the lastolite. I use the Kirk Enterprises Macro flash bracket in case you are interested.
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