Sunny Chung wrote:
Hi I just recently bought a ist* DL and have been using it for a
couple months...
Although now I wish I had the DS2, but it wasn't out then.
Anyway, I'm interested in buying a fast 50mm fixed lens, but I'm not
sure which ones are compatible.
I don't know what all the letters in front of the lens names mean and
which ones will work with mine.
I read something about apature rings being set to 'A' but could not
fully comprehend it.
Also I was wondering if other brands like sigma or even canon lenses
were compatible with
my ist* DL. Any information would help me a great deal, thanks. I
hope this is the way this digest
works, because I just signed up and have no clue how things run around here.
-Sunny
An SMC Pentax-FA is the newest class of Pentax 50mm lenses. They are
completely compatible with DSLR's and 35mm SLR's.
An SMC Pentax-F is the previous class of Pentax 50mm lenses. They too
are completely compatible, and essentially identical in operation. They
don't transmit MTF table data to the body, if you care (who does?)
An SMC Pentax-A lens doesn't support autofocus. You can manually focus.
Aside from that, compatibility is good.
An SMC Pentax-M lens doesn't support AF nor does it have an
auto-diaphragm. In other words, it doesn't support auto aperture.
Mounted on one of Pentax's DSLR's, you have to jump through an extra
hoop to get it to meter for you. Many people here don't see this as a
big deal. YMMV.
Previous to that, Pentax had SMC Pentax and Pentax K lenses. They'll
work about the same as a Pentax-M lens. Be sure to not accidentally get
your hands on a screwmount lens. They'll work, but require an adapter
that can sometimes be a finicky device.
If you want pretty much full functionality, get an SMC Pentax-FA 50mm
f/1.4 or f/1.7. The SMC Pentax-F 50mm f/1.4 or 1.7 is essentially an
equally acceptable alternative.
Dave
