audible said:
ok, so zeiss names like biogon, distagon, planar, sonar etc supposedly refer to the lens design and characteristics.
how about voiglander lenses? heliar? nokton? ultron? is it the same? or do the names just roughly correspond to max aperture, e.g f1.2 and 1.4 lenses are the noktons, 1.7 and 1.9 ultron etc?
(and while we're at it... summicron? summilux? forgive me... rangefinder newb)
The modern Cosina-built Voigtlander lenses do not adhere to the original names' meanings: here is a run-down to add to the other contributors obserbations:
Skopar referred to a Tessar-type design with four elements in three groups, designed for normal coverage.
Heliar, as explained, was a five-element lens in three groups, with the outer groups as cementd doublets. However: the original Heliar was made as a completely symmetrical design, and was soon replaced by the Dynar design wihich departed from complete symmetry; subsequent Heliars are closer to the Dynar than the original, and the Cosina-built Heliars are pretty much the only lenses true to the original optical configuration.
Ultron was a post-war design for covering the 35mm format, based on the double-gauss configuration, and designed for normal coverage.
Nokton was a high-speed standard lenss also with maximum aperture of f/1.5.
The name Lanthar referred to the use of "rare earth" Lanthanum glass in the lens construction, and most famous as the Apo-Lanthar which was a lens of Heliar/Dynar construction, of normal coverage, made for medium and large format only; it was also the first apochromat designed for distance work rather than low-magnification work. However, the Lanthar name was also used on low-cost three-element lenses fitted to 35mm and medium format cameras.
