Nokton, skopar, serenar, apo lanthar - lens names and types?

Paul Howell said:

Kodak used Ektar for it's top of the line lens, my 1943 Kodak Ho to Take Better Pictures described the 50mm 1.9 as 7 elements in 4 groups, it was designed for the Ektra. Kodak also used Ektar for the 3.5 100 that was fitted to the Medalist which I think was a 4 elements in 3 groups. By the 90s Kodak used Ektar for a lens on a point and shoot, likely a 4 or 3 element design.

Click to expand...

Paul, the Medalist's Ektar is a heliar type. In EKCo parlance Ektar means "our best in this line." Some Ektars (101/4.5, 127/4.7, 152/4.7) are tessar types. So are f/6.3 Commercial Ektars. The 203/7.7 is a dialyte type. The name Ektar has no implications for design type.

If you want a confusing mishmash, look into the Boyer lenses that bore the name Saphir.

AFAIK, S.K. Xenon is always double Gauss.
Their postwar Xenar lenses I've seen have always been Tessar clones, but a pre-war Xenar I saw looked like some other design.
BTW, the post-war coated Xenon lenses I've tested were very sharp. It's hard to believe they were designed with slide-rules.

Mark

This is so interesting to me. Thanks

Another pic from the Perfekta bakelite 6x6 single element lens camera. That single piece of glass is described as "Achromatic". I'm not sure what that means exactly, but what you get from it is a lucky dip. The camera is the boxy version of the Perfektas', and there's room in the top part of the camera to fit DIY flash sync contacts. The shutter blade, when fired, comes up into the housing where the DIY contacts would glued in, and trip them. The sutter would be open already when the contacts would be tripped, firing the flash. It's one of my projects for the future, and if it's sucessful, I'll certainly post about it here on Photrio.