While cameras have always had accessories, it was the Leica that pioneered the system approach. By creating a system of lenses and accessories, it made the camera more versatile, enabling the same camera to be effectively utilized in a broad number of applications. It didn't hurt that accessories produced additional income by their sales.
When Zeiss set out to compete with the Leica, they designed their system too. And like everything they did, they were compelled to better Leitz.
The scope of this section is so broad, I doubt it will ever be complete. If you have an accessory not shown here, it does not mean it is rare. It just means I haven't gotten to it yet.
Individual Focal Length
Optical finders in individual focal lengths are the most common finder for most manufacturers, but not Zeiss.
Available from early on, until the very end, these were popular with owners of multiple lenses.
These are prewar designs, and most cover two focal lengths.
These lack optics, and mask the cameras finder for 85 and 135mm lenses.
Zeiss tried to build a finder for every possible situation. Many are quite unusual.
Cut film Backs
Film Handling Accessories
Panflex Reflex Housing
Copy Stands and Reproduction Equipment