Tokina SZ 500mm f/8 manual focus reflex lens (mirror lens; introduced in 2021 or 2022) . List price $379 w/o T-mount; $399 with T-mount

Surprisingly good IQ, given the bad name mirror lenses have for IQ. But good IQ required care: mounted on a solid tripod, focused using focus peaking, electronic shutter with a 5-second delay, stable atmosphere, and the lens fully acclimated to the ambient temperature.

So... not for sports photography, but it still belongs in the lens database. https://tokinausa.com/products/szx-500mm-f-8-reflex-br-lens-only?_pos=6&_fid=359810715&_ss=c

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Mike Sandman