Two views of German amateur Percy Zahl's Schiefspiegler (closed construction).
Amateur Georg Dittie's instruments, a 150 mm Schiefspiegler (open construction) compared to a 150 mm refractor.
The 200/4000 mm Schiefspiegler of Stefan Schimpf. Note: The guiding refractor is a 5-inch, the Schief an 8-inch scope!
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