Vaughan,
The 200/4 and 300/4.5 were made in both single and later in multi-coating.
According to Lee Hawkins' Multi-Coating Cross Reference:
http://brashear.phys.appstate.edu/lhawkins/photo/multicoat.txt
the 200/4 went MC circa 10/78 and the 300/4.5 circa 12/81. Both apparently
are among the earlier lenses dating to circa 1974. Both TC's have
supposedly always been MC.
The 300/4.5 has 6e/4g making your book's stats suspect. With the lens and
group/element description, but without a cutaway, my guess is it's an
asymmetric which should have less flare problem than a symmetric. With
only a few groups you could easily use single coating (i.e., multi-coating
it wouldn't gain that much). Mine is an F.Zuiko (confirming SC and six
elements). I really don't feel complusion to sell it off for an MC
version. The contrast has been more than sufficient for me and it passes
my "unscientific-but-practical" sharpness test with medium speed
transparencies (Kodachrome-64 and Ektachrome-100) projected on a 50" screen.
The MC would be more important to me with a symmetric design, but still it
takes a back seat to condition and overall performance. The first coating
is what gains the bulk of coating benefit for light transmission and flare
reduction. Who knows what decision-making criteria were for the sequence
in which lenses went from SC to MC. Could have been any number of market
and competition reasons thrown in as well.
I think you will be pleased with both the 200/4 and 300/4.5 lenses. I've
hand held the 200/4; it's light and small enough, but it's also at the
limit of what I can hold steady in a well braced stance. The 300 is tripod
only, and I'd try to use the 2X-A with 135/2.8 if I needed something
approaching that length without tripod (in spite of Gary Reese's test
results on the combo).
The 180/2.8 and 1.4X-A TC are on the long-term wish list, but don't think
I'll sell the 200mm even if there's a 180/2.8 in the stable.
[For those not familiar with the general reasons for MC on a lens, no
single coating can cover the entire visible spectrum. An SC is usually
centered in the visible spectrum giving a yellowish or greenish cast. The
multiple colors usually seen in an MC are the centering of coatings at
various points in the spectrum to broaden the benefit of coating across a
greater region of the spectrum. I suppose one could/would also influence
overall color response with the center wavelengths selected for each
coating in the design.]
-- John
At 00:14 6/27/00 , Vaughan Bromfield wrote:
>Folks
>
>I dug out my big black OM System Lens Handbook last night. It is the
>October 1985 edition (marked C24E-Oct.1985 in the back) and has the 100
>f2, 180 f2, 250 f2 and 350 f2.8 lenses but not the 90 f2 macro.
>
>Anyway, I've discovered a few interesting things. Most lenses are
>specified as "multicoated" but there are a couple of exceptions:
>
[snip]
>
>Zuiko 200mm f4
>Not specified as being multicoated in the book, nor is multicoating
>mentioned in the text (page 148).
>
>Zuiko 300mm f4.5
>Not specified as being multicoated in the book, nor is multicoating
>mentioned in the text (page 152). Of interest is the note "the front of
>the lens features a luxurious 4-elements in 3-groups construction, with
>a combination of high refractive index glass and extraordinary partial
>dispersion glass to greatly reduce chromatic aberrations."
>
[snip]
>---
>
>We know how good many of these mentioned lenses are -- the 200mm f4 lens
>gets a good test report in particular and the 1.4X is a gem -- despite
>the fact that they are not necessarily "multicoated." I take this as
>indication that Olumpus really knew what it was doing with lens design
>and didn't just throw all the elements into the coating pot just because
>mc was trendy at the time. The quote "multicoated to minimise
>alterations in color balance" indicates to me that mc is more than just
>reducing flare and internal reflections. I for one am biased towards
>real-world lens test results and bugger what the specs say. I've put the
>200 and 300mm lenses on my shopping list.
>
>Hope this was interesting.
>
>
>Vaughan
>
>PS: I'm in Sydney Australia and seriously in the market for Olympus
>gear, after a year of self-denial. ;-) Even my wife is sympathetic!
>
>I'm after an OM1n, 28 f2.8, late 50 f1.4 or f1.8, 135mm f2.8 initially,
>later augmenting with 18 f3.5, 200 f4 and 300 f4.5. Of course I'd be
>tempted with an OM2n but not interested in the 2sp, 3 or 4. I don't have
>money for all at once. Looking around Sydney there is a bit of stuff but
>it's all a bit scruffy and/or way overpriced.
>
>PPS: I have a rubber 55mm slip-on hood for Zuiko 21 f2.0 in box (box is
>a bit squashed) and will swap for hoods for 50mm and 28mm f2.8. I no
>longer have the 21mm lens, sorry. <sob> I also have the 250 film back
>and darkroom loader (no reels though) for anybody interested. Asking
>prices around here are AUS$500 which is silly money, if interested I'd
>prefer to trade.
>
>
>Vaughan Bromfield
>Education Consultant
>Information Technology Division
>University of Technology, Sydney
>Australia
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