Recessed lens boards in which it is impossible to adjust the lens controls. Similarly, a Copal #3 lens mounted on a Technika-sized board, such that the slide fastener which holds in the board interferes with the lens controls.
Ball heads.
Human eyes more than 40 years old.
P.S. Dang, Tim, I was just appreciating my 8x10 BTZS yesterday morning. One man's poison...
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