Sumarongi
Registered Vaudevillain
A camera with lots more features than any mentioned so far, very reliable
is a Canon T90 with the M42 to FD adapter.
you lose auto diaphragm, but gain so much more its well worth the trade
lots of interchangeable screens
not only averaging, center, spot metering but also
MULTI SPOT METERING
Re features of the Canon T90:
Is there/are there
-- *Real* Mirror Lock Up?
-- Interchangeable finders?
-- Battery independence?
-- Mechanical shutter speeds, at least *one* please?

