The dark parts of the corrugated metal plates are created by dirt and/or corrosion. I can’t tell why only these parts are affected, but I guess there’re metal crossbeams behind the plates, where they're still bright, since there’re screws/bolts. And somehow this makes a difference. But whatever the reason is, I like the almost perfect pattern that is created by those dirty/corroded parts.
Unfortunately the fence at the bottom is a distraction. Especially since the plants are so chaotic. And of course the picture would be better without it. But when I crop it out I also lose a lot of the nice shadows of the staircase, which in my opinion adds to the pic. Also the position of the door would be too low then. What do you think?...
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