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Old February 18th 11, 11:15 PM posted to rec.photo.equipment.large-format
Donn Cave
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Default Lens Cell Cleaning

Quoth (Thor Lancelot Simon):
....
| On the other hand, maybe it's not "uncharacteristic". Wollensak made
| some awful Tessar lenses and so did a few others. Maybe Richard knows:
| is there something about the Tessar design that makes is particularly
| prone to manufacturing or Q/C error?

I believe one way to make a Tessar awful is to use it for LF
applications that require a larger circle than it really delivers.

While comparing the reputations of various Tessars, it might be
interesting to correlate with the absolute coverage circle -
that's not the right word, I mean the farthest extent of any
kind of coverage, irrespective of optical quality. My hunch
is that identical glass could have a better or worse reputation
depending on artificial cutoff from its mounting etc.

I was always more interested in tonal rendering, something I used
to read about with various lens types though couldn't positively
pick out of my own results. It seemed to me for example that
my 20" Calumet-Ilex (Tessar type I believe) turned out better
on color negative film than a 10" WF Ektar or a MC 240mm Caltar-S.
Not a conspicuous difference at all, and I didn't get real
scientific about it, but enough that I would use the Calumet-Ilex
when I could.

Donn