It has only vignette corrected by ACR. As You see this correction even with max values, it isn't perfect but I believe it is still usable. At APS-C f/8 gives a lot of DoF, which unifies corner's and center's sharpness. With FF there is such level of DoF with f/8, You need to balance between center and border focus, especially at such close-ups. This one if focused at borders, to illustrate if they are able to be sharp with BSI FF sensor and Hologon's lens design. It is taken handheld with steadyshot inside
I believe that Adobe software, lens profile based distortion's correction makes the outcome of Distagon 2.8/15mm to look artificially and not pleasant to me. I like it more better without geometric distortion correction, lens profile based vignetting correction works better :)
