see http://www.stevehuffphoto.com/2015/09/23/the-voigtlander-35-1-7-ultron-vm-leica-mount-lens-review/
Test done on Sony A7rII
Chrome and Black versions of the Voigtlander 35/1.7 M
the current production Voigtlander Leica Mount 35mm lenses,
35/2.5 P Color Skopar, 35/1.7 Ultron in black and chrome, 35/1.2 Nokton Version II
black Voigtlander 35/1.7 M Ultron mounted on Leica M-P
New optical formula, highly corrected very sharp fast 35mm lens designed for digital sensors
Great sharpness with minimum color shift
Styled like the 50/1.5 Nokton M Aspheric in classic chrome or black aluminum lens barrel
f/1.7 to f/16 in clicked half stops
9 elements in 7 groups, one aspherical
close focus .7meters with rangefinder coupling, scale focusing to .5 meter
46mm filter size
Dedicated LH-9 B Black or LH-9 C Silver Vented Lens Hood optional
Weight Chrome 11.6 oz, Black 8.4 oz
Size 50.6mm x 53mm
63 degree field of view on full frame 35mm
10 aperture blades for pleasing bokeh
Will fit ANY Leica M mount camera, as well as all Sony NEX, M43, Fuji X and digital mirrorless cameras via adapters
Test done on Sony A7rII
Chrome and Black versions of the Voigtlander 35/1.7 M
the current production Voigtlander Leica Mount 35mm lenses,
35/2.5 P Color Skopar, 35/1.7 Ultron in black and chrome, 35/1.2 Nokton Version II
black Voigtlander 35/1.7 M Ultron mounted on Leica M-P
New optical formula, highly corrected very sharp fast 35mm lens designed for digital sensors
Great sharpness with minimum color shift
Styled like the 50/1.5 Nokton M Aspheric in classic chrome or black aluminum lens barrel
f/1.7 to f/16 in clicked half stops
9 elements in 7 groups, one aspherical
close focus .7meters with rangefinder coupling, scale focusing to .5 meter
46mm filter size
Dedicated LH-9 B Black or LH-9 C Silver Vented Lens Hood optional
Weight Chrome 11.6 oz, Black 8.4 oz
Size 50.6mm x 53mm
63 degree field of view on full frame 35mm
10 aperture blades for pleasing bokeh
Will fit ANY Leica M mount camera, as well as all Sony NEX, M43, Fuji X and digital mirrorless cameras via adapters