Leica S2: axial chromatic aberration with Leica 70mm f/2.5 Summarit-S ASPH
Update!!!! With what I think is compelling evidence, I show that purple fringing is likely the result of ultraviolet or infrared (or nearby) wavelengths, using my Lupine Betty LED headlamp, which emits very little infrared, and likely no ultraviolet either.
Just published in DAP is an new page assessing axial chromatic aberration (purple fringing) to my review of the Leica S2. An aperture series and large crops are shown.
Also included is a comparison with the Coastal Optics 60mm f/4 UV-VIS-IR APO macro.
The comparison should be of interest to anyone wondering about purple fringing (eg Canon, Nikon or any other brand).