Lew if the question was why so many tight crops then the answer is because they look interesting, beautiful, they show up hidden beauty of flowers and... well that should be enough. whatever answer you'll find it'll be good answer - if you enjoy what you are photographing then you are doing the right thing. if others are enjoyed by what you are photographing it's even better. macro is showing more then close up (i know it sounds against logic) - it takes you exactly where photographer wants and it's very stright, in macro there is main object and almost nothing else. in close up you may find something else interesting then what photographer wanted to show you. i love macro because if you are creative enough you could show same flower in 10 photos and each one will be different, but absolutely different. you could operate not only with angles, but also with DOF - it works great with flowers
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