I was waiting for someone to bring up this point,
thank you Mr.Ernens. I believe both Roger and Frank
make good points. No doubt complex zoom and fast
lenses benefited most from MC development. Back in the
mid70's Pentax was the first to promote sales by
advertizing the advantages of their Super MultiCoating
Technology (SMCT) lenses. Other camera co's (N,C,O,M)
were quick to point out that they had been mc'ing
their lenses for some time. Pentax countered ; "Yes we
know that for years most quality lenses have been
coated with 2 or 3 layers on at least some air to
glass surfaces, but we put up to 7 very thin layers on
all surfaces." And so the controversy raged for years.
It looks like its still raging. For those of us who
shoot with moderate speed primes with only 5,6 or7
elements the advantages of MC are probably not as
apparent as with Ultra-wide,high speed or zoom lenses.
Most of my lenses are old SC Zuikos that are a bit
scruffy cosmetically. I suspect that is true for alot
of old timer Zuiks. If a person is just now building a
system, by all means try to obtain later MC glass, but
for those who already have a too expensive to replace
collection of older Zuikos, then use and enjoy them.
Just my two cents.
--- Frank Ernens <fgernens@xxxxxxxxxxxxxxx> wrote:
> Roger Scully wrote
>
> > If the coating really makes a
> > difference, it is only in a very limited way and
> probably only if the
> > photographer does not properly shield the lens
> from direct sunlight.
>
> It does make a difference, and here's why. I'll
> start with some figures
> from Robert Monaghan's web site
> http://www.smu.edu/~rmonagha/mf.
> He has a table
>
> uncoated SC MC
>
> glass-air surface 93
> % 99.8%
> 50 1.4 7 elt 41.8
> % 97.6%
> 14 elt zoom 17.5
> % 95.3%
>
> I don't know how he arrived at these figures, but
> suppose for
> the moment that each element has the equivalent of 1
> air-glass
> surface and you get:
>
> 7 elt 60.2
> % 98.6%
> 14 elt 36.2
> % 97.2%
>
> e.g. for 7 elt MC case transmission = 100 * (0.998
> **7).
>
> What matters here is not the transmitted light but
> the light that is
> *not* passed, because most of that becomes flare. So
> a seemingly small
> difference of 99.8% v. 98.3% translates to a big
> difference of 1.4% v.
> 11.3% with a 7 elt lens, through the magic of
> exponentiation. This is
> why multicoating reduces flare on lenses and why it
> isn't as important
> for filters.
>
> The other thing to take away from this example is
> that primes
> are better than zooms and slower primes with fewer
> elements are
> better that faster primes with more elements.
>
> If you prefer experiment to theory, all I can offer
> is that when
> I shoot into the sun over water late on a summer
> afternoon the
> 50 1/8 SC is unacceptable, the 35-70 Zuiko f/4
> better, and
> the MC Zuiko primes excellent. I shoot this way
> quite often.
> I don't have a lens hood for my 24 f/2.8 - would the
> Oly one
> vignette with a polarizer behind it anyway? - so I
> use my fake
> Akubra (hat) to shade it.
>
> Note that sometimes flare just manifests itself as
> overall reduced
> contrast, which you might not notice if printing to
> B & W. With
> colour slides you can get ghastly colour casts bled
> from
> sections of the image.
>
>
>
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>
>
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