In this blog post I will share a couple of unprocessed full resolution shots taken with the Voigtländer Macro Apo Lanthar 125mm f/2.5 SL for Nikon F mount (Ai-S). Although not a comprehensive lens review, it should give some idea of the performance of this lens, and the amount of vignetting (or lack thereof) to expect on the 44 × 33 mm medium format sensor.
The lens was produced by Cosina from 2001 to 2007 and is available in Canon FD, Nikon Ai-S, Minolta MD, Olympus OM, Pentax PK-A/R, Contax/Zeiss CY, and M42 mounts. It features two elements of anomalous partial dispersion.
In general, the lens has great sharpness in the middle, which drops off slightly towards the periphery. However, stopped down, it is acceptably sharp across the frame. The extreme corners are not very sharp on GFX, to be expected. There is some pincushion distortion. Longitudinal chromatic aberrations are generally well corrected, and superior to the 90mm f/3.5, but still visible in some shots, and inferior to lenses such as the Leica Apo-Telyt-R 180mm f/3.4, the Fuji GF 55mm f/1.7, and the Voigtländer Macro Apo Lanthar 65mm f/2.
Bear in mind, however, that it gets some vignetting at minimum focusing distance.