Pentacon's Exakta wide — the auto 29mm f/2.8, the mainstream late East German wide-angle.
The Pentacon auto 29mm f/2.8 is a wide-angle prime made under the Pentacon brand that consolidated the East German Meyer-Optik and Zeiss Jena works. Offered in the Exakta bayonet, it descended from the earlier Meyer Orestegon 29mm and became the standard mainstream wide of the Pentacon line. It gave Exakta owners an affordable moderately wide lens through the later years of the mount.
This is a manual-focus Exakta-mount lens with a 29mm focal length and a maximum aperture of f/2.8. It uses a retrofocus wide-angle layout inherited from the Orestegon design. The aperture is set on the barrel and, on Exakta variants, coupled through the mount's internal automatic mechanism, as the auto in the name indicates. Element count, filter thread and weight are omitted where they cannot be confirmed.
The Pentacon 29mm gives a moderately wide field suited to landscape, architecture, street and travel work, taking in more than a 35mm without the strong distortion of an ultra-wide. Wide open the corners are soft and improve markedly on stopping down to f/5.6 and f/8. Its rendering is typical of late East German wides, and it shares its optics with the earlier Meyer Orestegon.
Used Pentacon 29mm lenses are common and among the most affordable vintage wides. Inspect the glass for haze, fungus and separation, and confirm the aperture blades are dry and the ring clicks. Check the coatings for cleaning marks, which matter for flare on a wide lens, and test the focus for smoothness. On mirrorless via an Exakta adapter it is an inexpensive, usable manual wide.