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Old February 16th 11, 02:24 AM posted to rec.photo.equipment.large-format
Richard Knoppow
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On 2/14/2011 8:52 PM, David Nebenzahl wrote:
On 2/14/2011 3:57 PM spake thus:

On 2/14/2011 2:32 PM, Thor Lancelot Simon wrote:

In ,
wrote:

From my use, it's a very nice lens given a bad rap
mainly because
it was sold at a low price as a "novice lens". Who
wants that
when you can buy a pro lens? :P

Well, at least in the 1990s when the question arose for
me, it was
more like "who wants that when you can buy a nice clean
used
Commercial Ektar"?

I actually replaced a "nice clean" commercial ektar of
the same length
with this lens and got much better results at my
shooting apertures of
f16-f22. Maybe my sample was a bad one but the geronar
has much higher
contrast and "snappyness" to the pictures, especially in
difficult
lighting. Add to that a much better shutter, I don't
think I'd want 50
year old lens with marginal coatings in one of those old
supermatic
shutters over this one.


What do you mean, "marginal coatings"? Do you think they
flake off or
something?

Sorry, but it sounds to me as if you've bought the
marketing hype hook,
line and sinker when it comes to "advanced, space-age"
coatings. The
only "marginal" here is that modren coatings are
marginally better than
the old ones. Hell, even *uncoated* lenses (horrors!) can
perform
extremely well (under certain conditions).




I guess you missed the "difficult lighting? And yes those
early coatings were good, just not as good as later ones.
And yes I do use uncoated lenses too so understand your
point here. In tough lighting the ektar created low
contrast chromes.

I didn't make this judgment based on marketing. I
wouldn't have bought a geronar at all if I wasn't having
issues with the commercial ektar of the same length. I
have a 135mm WF ektar and the images it makes are nice and
crisp compared to the ones I was getting with the comm
ektar, hence I looked for a replacement. I have never
considered replacing the 135mm WF ektar, it works just
fine so don't thing older coating are rubbish.

Sorry if posting that -in my experience- this "novice"
lens performs much better that my old commercial ektar
did- rocks the boat of people who are sold on those old
lenses are somehow some sort of religious experience. I
could see nothing wrong looking at the commercial ektar,
maybe it was a bad one? I can only base this on my
experience. It was a -sharp- lens but didn't have the
contrast/snappyness this geronar has. So to say "-Blank-
old lens is a better choice" didn't work out for me.

Stephey


Both the Geronar and Commercial Ektar have the same
number of glass-air surfaces, six. Neither is a high flare
lens even uncoated. Multiple coating does reduce flare and
has much better anti-flare properties for color than a
single coating. The effect is more for color purity and
saturation than for overall contrast.
While its possible the coatings account for the
difference I think something else must be happening. What I
suspect is that the cement in the rear element of the Ektar
may have become hazy. This is a peculiar effect that I've
seen in other Ektar lenses. When examined under
magnification, and using grazing incidence light, you can
see that the cement layer has developed a sort of
orange-peel texture. You can see it using transmitted light
as a light haze but its effect on contrast is enormous.
Check your Ektar for this.
FWIW, the Commercial Ektars were designed especially for
color work and are almost apochromatic. Kodak was using them
to promote the sale of color film.



--
Richard Knoppow
Los Angeles
WB6KBL