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View Full Version : "Modern" lens design?



Mark Sawyer
1-Jul-2007, 12:45
Plasmats, Tessars, Dialytes, Dagors... all designs that are over a hundred years old. Are there any large format lenses whose basic design is relatively modern? Just wondering...

(I started thinking about this when it was pointed out to me that one can buy a new "state-of-the-art" apochromatic flourite-glass Petzval lens for astrophotography.)

Eric Leppanen
1-Jul-2007, 12:55
How about the SSXL's?

Ole Tjugen
1-Jul-2007, 13:05
The thing with LF lenses is that the old designs are just about perfect for just about everything - only a few super-fast super-wides really benefit from radically new designs.

Mind you - all the "old" designs have been extensively recalculated and "tweaked", and a late Schneider 210mm f:6.1 Xenar is a very different lens from and older Tessar-type - even if it's still basically a Tessar. And I'd swear there is an aspheric surface in my 150mm Germinar-W...

Arne Croell
1-Jul-2007, 14:03
Ole is right .. but apart from that the last "new" designs were:

The Zeiss Biogon/Schneider Super-Angulon-type wide angles from the 1950's with the large negative menisci on the outsides (again based on a Russian design by Roosinov from the 1940's named Russar, but only used for aerial cameras and 35 mm by the Russians, not for regular LF))

The Super-Symmar HM from Schneider in the late 1980's and

The related Super-Symmar XL from Schneider in the 1990's mentioned by Eric.

Bruce Watson
1-Jul-2007, 14:24
Plasmats, Tessars, Dialytes, Dagors... all designs that are over a hundred years old. Are there any large format lenses whose basic design is relatively modern? Just wondering...

Most aspherical designs are "new" (like the Schneider Super Symar XL series). There are some designs that you can make now because of some of the new glass types (higher refraction, lower dispersion, all that), and because of the improvements in coating technology (more elements, more glass/air interfaces). There are also some older designs that you can't make anymore (rumored anyway, but I haven't discovered which designs these might be) because some of the glass has been banned (used toxic chemicals to make).

The biggest improvments have been in manufacturing. Automation has allowed manufacturers to make compex shapes with excellent accuracy and precision.