FWIW, the new firmware I uploaded makes the C/V 21/4 , 24/4 and the Zeiss 21/2.8 quite usable on the M9 without the need for Cornerfix (mostly). The 21/4.5 still needs some help though. I just ran some quick test shots with the following lenses wide open.
C/V 15/4.5 (M-mount, LTM 2 samples, identical result. Still needs cornerfix)
C/V 21/4 (fine) !!
C/V 24/4 (fine) !!
ZM 21/2.8 (a _very_ little green edge-I shot a white wall in the shade o/w hard to notice. In general, I will not be correcting this)
ZM 21/4.5 (still needs cornerfix)
ZM 25/2.8 (fine)
Leica 28/2.8 (fine)
Leica 35/2 v. IV (fine)
ZM 35/2 (fine)
ZM 35/2.8 (fine)
Both vignetting and red-edge appear _very_ well controlled. I know that some have had issues with the firmware update but mine went very smoothly, and I have to say, the camera is much more useful with these wides. Leica gets a very big thumbs up from me for the improvement. Loved the camera before. Over the moon about just using the wides.
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