------------------------------
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
-
This message is from the Pentax-Discuss Mail List. To unsubscribe,
go to http://www.pdml.net and follow the directions. Don't forget to
visit the Pentax Users' Gallery at http://pug.komkon.org .