A lot of folks don't remember the old "Cold War" days, which explains the confusion.
When Germany was split into 2 halves after the 2nd world war some of the Zeiss plants were in the western sector, but some were in the East & so run by the Soviets.
The estern factories became Zeiss (Jena) , & Carl Zeiss (of Zeiss Ikon fame) in the west.
Add a little Soviet capitalism & you have FED (owned & operated by Fedor Illich Dzerjinski, the "father" of the KGB, & the man Dzerjinski square in Moscow is named after) marketing Zeiss (Jena) products thru his own privately-owned optical corporation.
In reality the glass & optics design on these was every bit as good as the Carl Zeiss (west) product, but the mechanics were a bit heavy-handed, Soviet style. Some of the other FED products were cameras, telescopes & microscopes, once thought of as "cheap russian copies" but now becoming collectable in thier own right.
If you do a web search for "Zenith" (pronounced gennitt), Zorki, and FED you'll find a bunch of the background. The Zeiss (Jena) Factories most popular product in the West was the "Praktika" Brand of cameras.
