I was strolling through the town on the weekend and came across a pre-owned Bower(Rokinon/Samyang) 8mm fish-eye lens for dirt cheap.
Designated for ef-s mount but fits ef full frame bodies and with a little surgery (cutting off the built in lens hood, lots of videos on youtube of various ways to get it off) produces the classic circular fish-eye image on FF bodies.
Right now, with its lens shade attached it clips the image to mostly rectangular.
Anyway shot down the stair case of Vistek in Toronto shortly after I obtained it.
EOS 5d-mkii, iso:500, 1/50's f/5.6, focused at 1 meter (lens is all manual operation)
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