Ihagee: Kine Exakta

When: 1936
Why: First production version of 35mm SLR, first system SLR, first interchangeable lens camera with bayonet lens mount

Ihagee was already known for the first 127 film SLR in 1933 and just in three years they introduced a first 35mm SLR too. But here is why I had to add "production" word: the first 35mm SLR prototype was a Soviet Union camera named Sport (Спорт) in 1934. Unfortunately it didn't go into production for another three years, so Ihagee stepped in first.