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Two totally different things.........

Bus stop ->>> pick up drop off, even with high class hookers...such as yourself, I mean, if you selected that path.

F-stop->>> focal length of your lens.

It appears your lens is blurry.

Don't even think about explaining what an f-stop is.

Don't * (typo correction)even think about explaining what an f-stop is.

I wouldn't waste my energies on such a fruitless endeavour. Learned that lesson long ago...let me count the years.....oh yes, around twelve or so. Always best to abandon ship and swim for it.