sevo
Fokutorendaburando
The Praktica with a (optional) spring motor drive was the Praktina - not really a Praktica, as it came later and was a incompatible product line. A separate up-market model line pitched against the Exakta (by a then still privately owned competitor) and Alpa rather than the Praktica and Contax D. It probably wasn't its advancedness that killed it - the ongoing mergers into one single state-owned camera industry that happened in the GDR around then did not give it the time needed to establish itself. Creating incompatible versions of the mount with every model update can't have helped matters either.