The 560 g Leica 75 Summilux was created in 1980, and features 7 elements in 5 groups. It was manufactured in Canada and later in Germany. Thanks to Dr. Walter Mandler (whose specialty was designing Double Gauss lenses), this lens has been pushed to the limits in non-aspherical Double Gauss design. This quality has allowed the 75 Summilux to stay in the Leica catalog all the way up till 2008. That’s a full 28 years before this lens was finally retired. And for those who don’t know, Dr. Mandler designed over 45 lenses for Leica. In fact, he helped Leica create the first ever 35 ƒ1.4 lens for any 35mm format. Dr. Mandler also designed the 50 Summilux, which was unsurpassed and remained in the Leica catalog for 40 years until new aspheric fabrication techniques allowed for improvement. Lastly, the design of the 75 Summilux derives from the classic Noctilux, which only adds to this lens’ legendary status……..

Source: findingrange.com

LEICA 75MM F1.4 SUMMILUX-M Patrick Leong