Not so complicated, in fact, and explained here so many times:
- F&H manufacture the Sinar Hy6, the Leaf AFi and the Rolleiflex Hy6, including all the mechanical accessories
- Sinar/Jenoptik manufacture the digital backs, including all the accessories (adapters)
- this Hy6 camera does accept over 45 different lenses, starting with all the Schneider and Zeiss 600x lenses to the new Schneider AFD lenses and Zeiss AFD.
So many names - Sinar, Leaf, Francke & Heidecke, Rollei, Zeiss, Jenoptik, one needs a complete scrabble set to keep up with all the labels found on pieces of this camera It's clear that cooperation in europe