The Leica 28mm f/2.8 Elmarit-M ASPH is a dimunitive jewel with very low distortion. But even on Sony NEX (APS-C sensor), it had its issues. But on the Kolarivision A7R.MOD it offers a nice boost in quality over an unmodified Sony A7R.
In Guide to Leica:
Includes HD images up to 4320 pixels across the f/2 - f/11 aperture range as well as HD crops from both the stock A7R and Kolarivision A7R.MOD can be easily compared. With commentary.
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