wow, i was looking a macro photography forum last night......my macro set up has nothing on what the pros have.
combine the sigma 150mm lens, plus all 3 kenko extension tubes, and an external flash ring, AND a mini tripod or some other sort of grip. craaaaaaazy.
but i did read something interesting, that you get better picture quality by going with all 3 extension tubes than having to crop 100% without them. thats very interesting.....no wonder they get those crazy closeups of bugs to look so clear.
you also need a ton of light to keep the shutter spead fast enough....as the bugs move too much for a long exposure. ;)