Hi, I'm Moose and new to this list, courtesy of a a short e-mail
conversation with Tom Scales.
I saw my first OM-1 soon after they came out and immediately got rid of
my Nikon Ftn and bought a chrome, pre MD OM-1, so I'm approaching my
30th Oly anniversary. Shortly after the OM-2n came out, I bought a black
one and the OM-1 became my backup. With the 50/1.8, 35-70/f3.6, 100/2.8,
Tokina RMC 80-200 f4.0, Vivitar 28mm f2.5 and a T-32, I was a happy
photograhper for many years. Then I found I had more time and money than
when I was younger and wanted to get back to photography as fun and
creative art. Then I discovered eBay and the rest is (sordid?) history.
What I really need is a 12 step program, but I'm here instead. I don't
think I'm in Tom's league, but.... I do have many OM bodies from the
OM-1 that started it all through a 4Ti. And lenses!! Do I have lenses?!
They run from 18mm to 1000mm, with way too many stops and duplicates in
between. Maybe I'll let you know more when we know each other better -
and I've taken an inventory and start selling off the excess.
In the meantime, I'd like to reply at way too much length to:
---------------------------
Please don't tell me there is a 2/90 OM for sale on ebay, please.... ;)
There is a 50/2 macro, first in a long while. Sell those investments.
Mortgage that Cello.
tOM
---------------------------
Actually, there are 2 50/2s on eBay at the moment. What I don't get is
why it's such a big deal. For a collector, ok, but for a picture taker???
Back in the archive, someone suggested a 135/2.8 was better for distance
than a 135/4.5 macro... and somebody else said the equivalent of
"Plueeeeze!!".
I'm not immune to the "Newer, faster, more expensive is better."
syndrome. However, there is more than that to this subject. In the
current state of lens making, it is not possible to make a single lens
of a given focal length and speed that is BOTH as good focused at
infinity as a lens optimized for infinity AND is as good at 1:1 as a
lens optimized for 1:1. In the case of Zuiko, they have a set of 'pure'
macros optimized for close-up work with a bellows. They also have the
two 50mm and the 90mm 'macros' with helicoid mounts that focus to
infinity. These are obviously compromises somewhere between 'pure' macro
and conventional lenses. I have a couple of the 50/f3.5s and a Tamron SP
90mm macro. (By the way, I've heard that the later version of this lens
is optimized for a greater focal distance than the earlier one; either
to cater to it's most common use or to get better ratings in magazine
tests run at long focal distances.) Used on a copy stand, they do a
superb job of preparing slides for college lectures. The questions are:
Should I use a 50/3.5 for regular photography instead of a 50/1.4 or
even 50/1.8. Should I buy a 50/2.0, for macro work? ..for regular
photography?
I already know the answers from many years of photography and designing
equipment for highly specialized copy and projection work years ago, but
I think it's also easy to show.
First of all, for actual close-up work, no matter how much fast a lens
may be wide open, it has the same depth of field at any f-stop and
focal distance as any other lens. As a practical matter, all close up
work tends to require small f-stops. This is obvious for small 3-D
objects. Everyone who walks up to a flower and tries to get a good
close-up quickly finds that a small f-stop is needed. However, it is
also true to an important extent for copy work of flat objects. I know
that we all think our cameras are perfect and the distance from the lens
to the focusing screen is exactly the same as the distance to the film..
and the film is perfectly flat... and our lenses have no curvature of
field... and our camera is absolutely square to the copy... and our our
can see focus perfectly after hours of work. The truth is that good copy
work is also done at smaller apertures. So a faster lens per se dosen't
have any advantage for macro and copy work.
For work at greater focal distances, there is an enormous amount of good
information on Gary Reese's lens test page. His tests of a flat subject
at a 1:40 magnification ratio are excellent for judging quality for
everyday photography. So lets look at some 50mm lenses. I've converted
Gary's comments on contrast and vignetting into columns:
50mm f/2.0 Zuiko Macro (multi-coated) 50mm f/3.5 Zuiko
(multi-coated) 50mm f/1.8 Zuiko ("Made in Japan" variant)
50mm f/1.4 Zuiko >1,100,000
OM-2000 with mirror and aperture prefire. OM-4 with mirror and aperture
prefire OM-2S with mirror and diaphragm prefire OM-2000 with
mirror and diaphram prefire.
Distortion = none Distortion =
very slight pincushion Distortion = slight barrel
Distortion = none
Aper. Cent. Cor. Cont. Vign. Aper. Cent.
Cor. Cont. Vign. Aper. Cent. Cor. Cont. Vign.
Aper. Cent. Cor. Ctr. Cont. Cor. Cont. Vign.
f/1.4 B
B M ML D
f/2 B- B- M B
f/1.8 B C
H C- f/2 A- B H
H B
f/2.8 B- B M ?
f/2.8 A- B+
H A- f/2.8 A A- H
H A-
f/4 A- A- M ? f/3.5 B-
C MH A- f/4 A+ A VH
A f/4 A A H
H A
f/5.6 A- A M ? f/5.6 A
A MH A f/5.6 A A- VH
A f/5.6 A A- H
H A
f/8 A+ A+ MH ? f/8 A+
A H A f/8 A A- VH
A f/8 A- A- H
H A
f/11 A A- MH ? f/11 A
A MH A f/11 A- B+ H
A f/11 A- A- H
H A
f/16 A- B+ M ? f/16 A-
A- MH A f/16 B+ B H
A f/16 B+ B+ H M
A
f/22 B+ B+ MH A
It's easier to see the forest when the trees are lined up like this. I
know these comparisons aren't really valid at the 1/3 grade level, but
just for fun... I converted all the resolution grades to numbers, A+=9,
C-=1 and the contrast grades to numbers, VH=5, ML=1. I then added up the
two resolution scores for each f-stop for each lens and selected a
winner based on high score. I then added the contrast scores to the
totals. Since I use only one contrast score and the contrast numbers are
lower, this total is still heavily resolution rated.
Here are the winners based on the exercise:
f-stop Resol. R & C
f/1.4 f1.4 f1.4
f/2 f1.4 f1.4
f/2.8 f1.4 f1.4
f/4 f1.8 f1.8 (scores of all lenses basically a tie)
f/5.6 f3.5 f1.8
f/8 f2.0 f2.0+f3.5
f/11 f3.5 f3.5
f/16 f3.5 f3.5
f/22 f3.5 f3.5
Now, some of the scores are too close to be meaningful, but I think you
see the point, the f1.4 is the best general use lens. The question of
best for close-up lens is not quite as clear, but based on the above
discussion of the practical needs and especially the availability of
f/22 for additional depth of field, I think the f3.5 is the best choice.
Add in the large cost and availablity difference and it's no contest!
Cheers,
Moose
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