"Don Pyeatt" wrote in
:

I have an older lens, marked Carl Zeiss Jena, Flektogon 4/25. Is this
lens compatible with, or adaptable to, a modern DSLR?

I don't know anything about the particular lens, but I'd given even money
on it being adaptable, at least to most Canons or Nikons. I use a number of
classic lenses on my Canons, including Zeiss C/Y, Leica, even a Schneider
enlarging lens on a cobbled up bellows system.

You could pop over to Fred Miranda's website and ask in the "Alternative
Digital Systems and Lenses" forum.