On Wed, 23 Aug 2017 19:51:59 -0700 (PDT), Ivan Vegvary
wrote:

What's the easiest app/way to attach a single photo to a message to this group?

Put it on your website or one of the free photo sharing sites, Ivan.
Usenet doesn't "do" photos except in the binary-only groups.

--
Shake off all the fears of servile prejudices, under which weak minds
are servilely crouched. Fix reason firmly in her seat, and call on her
tribunal for every fact, every opinion. Question with boldness even the
existence of a God; because, if there be one, he must more approve of
the homage of reason than that of blindfolded fear.
-- Thomas Jefferson