Rodenstock / ALPA HR Alpagon 5.6/23 mm, LB, in X-Shutter - custom made for ALPA by Rodenstock.
The HR ALPAGON 23mm is the first choice for those photographers who need to cover as wide an angle as possible with a single "single shot": On a 40x54mm sensor (like the IQ160 / 260/360, IQ180 / 280/380 or IQ 1 100 / IQ3/4 100 and later IQ4 150 from Phase One or the H6d-100c from Hasselblad), the diagonal field of view is approximately equivalent to a 15mm "full-frame" lens (35mm full frame).
While such image angles on (medium format) SLR cameras can only be realized with large optical "artifices", ALPA technical cameras allow a much smaller distance between the rear lens and the sensor. This freedom allows optimization for highest resolution and sharpness. Shooting with the HR ALPAGON 23mm impresses again and again with its richness of detail and the lively micro contrasts. The on-edge color shifts that occur in modern high-resolution sensors (due to micro-prisms in front of the pixels) can usually be easily removed using the "Lens Cast Calibration" function. Due to the large front lens, the use of a suitable lens shade is recommended.
The HR ALPAGON 23mm is the ideal lens, especially for spectacular landscapes and narrow interior spaces.