Backstory:
My dentist friend (in Naval Reserve--an affliction, I wot) found self at Cam Ranh? Bay [Vietnam Era that is] serving troops
--also running amok in The P.X. [Post Exchange==near-free Stuff! Everywhere.]

Consequently.. I made the procession through the 'Photomic' series of various modular (eyepiece + light sensors) etc. to my last:
a shiny-black F-2, the über Portrait 105mm ƒ2.5, a 24mm and others. Leather Nikon bag/box w/lens mounts!
(Note that today's mondo-Zoom lenses with pretty un-shabby specs-all-along their glide path: were still
just gleams in the inner-eye of the corporate-constrained optical-Whiz-designer.)
'Lectronics had not fully Struck. Yet.

Never would I have paid US retail for any of this, natch--when I finally unloaded years later: most-all sold for more than I'd paid
(I keep machines in proper fettle; habit from whatcha gotta do to do Big Science, etc.)

BEWARE: a one could ... lose wife/cat/house/BMW/Veyron! ... should the wonders of Optics Post-Grad Course-666 intrude and overtake
the endorphin generators and their ceaseless urge for further gratification-at-any-Cost.
ie. 'Intelligence' in these waters is as irrelevant as was Spock's ... in-heat as only Vulcans can Be--in the affair of
er? the Compromised Bethothed/then that duel with Kirk/thence.. his 'death'.
Shiny/Shiny--the new designer-Diacetylmorphine?

None is immune sez I, in possession of a mere mondo-oscilloscope of Canon/Nikon/Tektronix quality,
once sold for >$25K ..but I paid <$500..