Abandoned plants are very cool to shoot in. Be careful they often have aspestos and other nasty items kicking around. Remember getting cool photos is one thing but never never place your self into harms way. Keep alert and let someone know where you are and when you will be back.
I work professionally, and I teach photography in a university. I too love macro work working as a pro allows me to have the gear I would like usually. I run nikons for the most part but keep a few Fuji pro bodies around when you need that extra range. I guess I am spoiled a bit having a 60 micro, 105 vr micro and a 200 macro. They are all very good the 60 being the bench mark for most macro lenses. In truth gear is just gear and the person behind the glass makes the photo.
here is a couple of fun ones...
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