------------------------------

Dan,

I don't own the Vivitar Close Focus 28/2; that's a different lens, more
closely related to the Kiron than to the Series 1 1/9. However, here are
the specs for seven fast third-party K-mount 28s, shown together with
Pentax's 28/2 offerings:

               Min.Focus      Max  Min.  Filt      Diam.     L.   Wt,
Elem.     Diaph     Years          Floating
                              Mag. Aper.      Size      (in.)     (in.)
(oz) Grps.     Blade     Made      Element(s)?

Cosina CMC 28/2     0.3 m (12 in.) 1:7   f/16      49mm      2.5  1.9  7
8/7  ?    79-81+?   No
Kiron 28/2          0.3 m (12 in.) 1:7   f/16      55mm      2.5  1.8  10
8/8  ?    80-82          Yes
Pentax 28/2K SMC    0.3 m (12 in.) 1:7.5      f/22      52mm      2.4  2.8
14.8 9/8  6    76-80          Yes; FREE and non-
Pentax 28/2 M  0.3 m (12 in.) 1:7.5      f/22      49mm      2.4  1.7  7.6
8/7  6    80-84          No
Pentax 28/2 A  0.3 m (12 in.) 1:7.5      f/22      49mm      2.4  1.7  7.6
8/7  6    84-88          No
Sigma 28/1.8 Asph   0.3 m     (12 in.)   1:7  f/22      58mm      2.7  2.4
12.3      9/9  7    92?-01?   No
Sigma 28/1.8 EX
DG Asph. AF Macro   0.2m (7.9 in.) 2.9   f/22      77mm      3.3  3.1  16.9
10/9 7    2001-          Yes
Vivitar 28/1.9:     0.3 m     (12 in.)   1:7  f/16      58mm      2.7  2.7
12   ?/?  ?    78-80          Yes
Vivitar 28/2 CF:    0.3 m (12 in.) 1:7   f/16      55mm      <2   ??   09
?/?  ?    83-?      Yes
Vivitar 28/2   ? in.     (? in.)         (?)  f/16      55mm      <2   ??
08   ?/?  ?    79-??          No


Notes: All lenses are multicoated; all are PK mount, except the two Sigmas
(PKA).

It's not clear why Pentax rates its lenses' max. magnification as 1;7.5
while other brands having the same minimum focusing distance claim 1:7.

As the table shows, a floating element does not necessarily allow a shorter
close-focus distance. More typically, it is used to minimize aberrations at
close focus,

The Vivitar 28/2 close focus is hard to find; Many Vivitar 28/2s are
advertised, but fewer than 1 in 20 are advertised as close focus, so I
assume that the close focus version proudly states its capability in the
etched letters. The CF model is regarded as a far superior lens, arguably
worthy of the Series 1 name.

The Sigma manual-focus model was discontinued circa 1998. The AF version is
still available but is likely to be phased out in favor of the
just-introduced 28/1.8 EX DG, which features LD glass and internal
focusing. Weight and focusing distance are based on Popular Photography's
test; Sigma lists the weight as 10.2 oz.

Based on my personal experience, Kiron's 12-inch close focus spec appears
conservative. I would place it at 10 or 11 in.


------------------
Date: Fri, 9 Mar 2001 16:38:13 -0600
From: Dan Scott <[EMAIL PROTECTED]>
Subject: Re: fast kiron on ebay

Hi Paul,

Would you happen to know the minimum focus for your Yivitar 28/Close Focus
and max magnification?

Thanks,
Dan Scott
[EMAIL PROTECTED]


Paul Franklin Stregevsky
[EMAIL PROTECTED]
W: (703) 834-4648

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