>>2905590The rules kind of get thrown out the window with macro for a few reasons:
1) an f/2.8 macro lens isn't f/2.8 when focused down to 1:1. It's closer to f/5.6, which means that your shutter speed is invariably slower. it doesn't help that you're usually shooting in shadow or dark corners or in shade. this isn't always true.
2) handshake and relative subject motion is massively increased when shooting at 1:1, so the "1/focal length" rule kind of gets thrown out the window.
Neither of these are hard rules, and you CAN shoot a 105 macro lens handheld (pic related, 105 2.8 ai-s on a d800), it's just a lot harder and I want to manage your expectations. Either way, you'll find out that a lot of macro photography requires flash, which makes both of the above rules moot.
