Rolleiflex

Introduction
Although my first serious camera was a Russian Zenit TTL, I consider myself a photographer of the digital era. In the past 10 years, I have been taking pictures exclusively with various types of digital single-lens reflex (mostly Canon) cameras. So starting to take pictures with traditional twin-lens reflex (TLR) cameras was a very interesting experience for me. For people who are unfamiliar with how a TLR camera looks, the picture below shows a studio "portrait" of the Rolleiflex 2.8F, one of the most legendary TLR cameras in the history of photography.

Rolleiflex 2.8F Planar, January 2013
Fuji X-E1 with Fujinon XF 35 mm f/1.4R @ f8, 1/125
The special feature of TLR cameras is that they have two lenses of the same focal length with their focal planes aligned. The lens at the bottom of the camera is the one that takes the picture (often called 'taking lens'), while the other is used in the viewfinder system.
Twin-lens reflex cameras are certainly an odd species nowadays....