It appears that Pentax makes both a 50 F1.4 SMC
(52mm filter) and a
50 F1.4 SMC-M (49mm filter). Which one is better
optically, build,
etc.?
Steve Pearson
>They're identical optically (although the
coatings *may* have been improved
>in the M version). The SMC 50 f1.4 (52mm filter)
has better build quality.
Mark Roberts
Hmm.... I thought Boz uncovered some sort of hard
evidence that they
are slightly different?
William in Utah.
Indeed, M 50/1.4 is a new design. The lens diagram
for the K and the
M lenses are different but for some reason the M
diagram ended up in
Boz's site as the K diagram. I sent Boz many
diagrams in 1998 so I
may have sent an M diagram for the K one, or Boz
made the mistake of
taking the M one for the K lens. Anyhow, the
confusion persisted for
years until I noticed on the PDML that it was said
repeatedly that
both lenses were the same. In july I found the
origin of this
confusion:
Hi Boz,
I have been puzzled for a long time by this
repeated statement that
Pentax 50mm 1.4 K and M share the same optical
design. I knew it
wasn't the case. I even wrote to the list once but
nobody took
note. I recently discovered why: PDMLers believe
in Pope's
infallibility.
As our K-mount's Pope, I request you to check these
3 jpegs (and see
that the optical design presented on site for the K
lens is in fact
the one for the M lens) and write a papal bull to
rectify the
erroneous statement.
I know you secretly believe, like most of us, that
all Pentax
50/1.4s are pagan gods...
Truly yours,
The Hooded Monk
P.S. I still have to scrutinize other pages of The
Site.
The Pope agreed the give me an audience.
Hi Andre,
As our K-mount's Pope, I request you to check
these 3 jpegs (and see
that the optical design presented on site for
the K lens is in fact
the one for the M lens) and write a papal bull
to rectify the
erroneous statement.
Amen, I have seen the light! I will make the
necessary changes, but it
will take me another 2 weeks or so. (...)
P.S. I still have to scrutinize other pages of
The Site.
Study the Pages, my son! This is the only way
towards him...
Halleluja!
Boz
Then came the Papal bull...
Date: Sun, 21 Jul 2002 11:29:38 +0200
From: Bojidar Dimitrov <[EMAIL PROTECTED]>
To: PDML <[EMAIL PROTECTED]>
Subject: K50/1.4 != M50/1.4 != A50/1.4
Hi all,
The resolution tests have already confirmed this,
but for some reason we
were too lazy to really notice it. However, after
careful studying of
the optical diagrams of the K, M, and A 50/1.4
lenses, I have come to
the conclusion, that all three of these emply
different optical
designs. I have received detailed scans of the
optical diagrams of the
three lenses, and they are indeed slightly
different. You notice it
only after you stare at them side by side.
The next KMP update will feature the three optical
diagrams, but the
imatient ones can take out a few of the "Pentax
Lenses and Accessories"
booklets and compare. Until now I had simply
assumed that the
differences (and I HAD seen them) were simply due
to the different
printing quality of the various booklets. But now
I own a booklet where
the diagrams of the K and M lenses are one above
the other, and the
printing quality is the same. The differences are
there.
Thanks to Andre Langevin for pointing this out!
Cheers,
Boz
Now you have the whole story!
Andre
--
