You asked
Leica summilux m 35mm f 1 4 asph vs voigtl nder nokton vintage line 35mm f 1 5 aspherical?
Both are 35mm manual-focus primes for full-frame Leica M bodies, so the choice comes down to how much you want to spend on the last bit of speed. The Leica Summilux-M 35mm f/1.4 ASPH is the one I'd pick if you shoot in dim rooms or want the most background separation. The Voigtländer Nokton Vintage Line 35mm f/1.5 Aspherical is only a third of a stop slower, which is hard to see in practice, so it's a sensible choice if you'd rather keep the difference in your pocket.
Both fit the same Leica M bodies, such as the Leica M11, and both suit environmental portraits and street work. For more on that, see portraits.
Written by Claude from this site's pages.