C.H.Ling wrote:
> ----- Original Message -----
> From: "Moose" <olymoose@xxxxxxxxx>
>
>
>> C.H.Ling wrote:
>>
> OM 200/4 vibration problem is mainly due to aperture stop down lever, the
> problem should not exist on E-1 and shutter vibration is not as critical.
>
I agree.
> It seems not sample variation for 180/2.8 in Gary's test, I see different
> cameras were used.
Oops, my mistake. I copied results for the 180/2.0, not the f2.8. The
only 180/2.8 test I would use is the one with mirror/aperture prefire
and lens support. However, it isn't as good as the equivalent 200/4
tests - although the differences aren't significant by Gary's rules. The
200/4 is in any case not worse.
> If you believe about sample variation then we can forget about all data.
>
I believe sample variation is unavoidable. In factory new units, I
believe it was quite small, and probably insignificant for all but the
occasional outlier. With used lenses, I think the possibility of a below
average sample is increased, as the effects of handling show up in some
samples.
>> Gary's test showed the 200/4 with 2XA, OM-4 with mirror/aperture prefire
>> and lens support to be quite decent, on a par with the 180/2.8 and 2XA
> 180/2.8 was not design to be used with 2XA.
>
Nevertheless, this thread started with two images of birds taken with
200/4 and 2XA. You are the one who raised the 200/4 vs. 180/2.8 issue.
Neither has the FL needed without a 2x. So I naturally looked at the
performance of both with 2XA. In fact, in Gary's tests, they perform
comparably both with and without the 2XA.
>
>>> and only used once or twice in E-1, it was ok but not as sharp as other
>>> Zuikos.
>>>
>>>
>> This is a very interesting area. Have you read the dpreview tests of the
>> Canon and Nikon 70-200/2.8 lenses? VERY different results. The Canon wins
>> for FF, the Nikon for APS size sensor. Comparing lenses across formats
>> apparently isn't as easy as one might think. Results of the 200/4 on 4/3
>> format may or may not mean much for performance on FF film.
>>
>
> My experience was based on the same sensor (E-1/E-3) so APS vs FF does not
> apply.
>
I believe it does, as you are using results with an even smaller sensor
to compare to results with FF film. If you magnify each the same amount,
so that the 4/3 image is half the height of the film image, there's no
problem. If you magnify the 4/3 image twice as much, the the image with
the same lens may look quite different from the two systems.
>> I'm not saying your experience isn't true, but that someone else, in highly
>> controlled tests, had different experiences.
> I belive Modern Photography Tests were also performed under well controlled
> condition. You can found the test results in Lee Hawkins' Olympus FAQ:
>
> http://brashear.phys.appstate.edu/lhawkins/photo/mp-zuiko-tests.txt
>
Thanks, I had forgotten that link. And it may contain the answer
"200/4.0 SC (4/73 p.99 (w/OM-1 test pp. 98-100)):" . The numbers are
very low, not in keeping with Gary's tests or the results generally
posted on this list over the years I've been here (which are fewer than
yours).
If the test was indeed performed using an OM-1, whereas the test I
referred to was performed with an OM-4, mirror and aperture prefire and
the Bogen lens support, that alone would account for the differences.
> Sharpness and resolution can be very different, if you are not using
> resolution chart you may only get an impression on the lens sharpness but not
> true resolution.
>
I agree. What we see as sharpness is a combination of sharpness and edge
contrast (and saturation, in color). alens with very high accutance may
appear sharp at modest enlargement even with modest true resolution. The
reverse is aslo true. A lens resolving 300 lp/mm, but with low accutance
will appear very soft. (Although the game changes with digital, where
LCE could bring up the contrast.) I actually think Gary's test subject
was a pretty good one for judging practical resolution and contrast for
film cameras.
-------------------------------
I just don't believe that Modern's test is representative of the
capability of the lens in general. Whether a result of use with an OM-1
and no vibration control or simply a bad sample, I can't know. I do know
your results with 200/4 and E-1 aren't universal.
I can quote AG from February of this year.
-------------------------------------------------------
On my E-1. the 200/4 is the cat's meow, but on the OM bodies it is
excellent, but problematic at times.
-------------------------------------------------------
And from Nov. last year:
-------------------------------------------------------
Hi all. Any opinions on what OM lenses are the best match to
> digital E-series bodies?
Most.
> > One in particular I am look at is the 1:4 f200mm.
This is one of my favorite lenses on the E-1. Here are a few examples:
<snip examples no longer on AG's web site>
-------------------------------------------------------
And Nov, 2006:
-------------------------------------------------------
I'm still using my 200/4 as it really does such a fine job on the E-1 for
sports photography.....
Totally serious here: My 200/4 really is an outstanding little lens for sports
work. In 35mm parlance, it's a 400/4 which you can handhold and slip into a
jacket pocket! Sharp? Sharp enough for the E-1's sensor.
-------------------------------------------------------
On the other hand, Ian reports in Mar. 2007:
-------------------------------------------------------
... my recent purchase of 300/4.5 works well with the E1 much better than my
200/4 which is really soft ( I
guess I have a bad one though because it's a silver nose so should be good)
-------------------------------------------------------
Chuck has posted that for many years his only lenses were a 50mm and the 200/4
and that the majority of his sots were with the 200/4.
-------------------------------------------------------
So did you and Ian end up with crappy 200/4s, Chuck and Gary with good
ones and AG with the magic one? I have no idea, but I am pretty sure
that the 200/4, used correctly, is not on average below the standard of
the other Zuiko (non-white) teles.
Moose
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