If I carefully observe the chromatic aberration of the Leica Summilux M 50mm/f1,4 2nd generation, I would notice the S curvature line! Fully compensated at f2.0, then returned to zero point at f1.4, with the aperture fully open. I have never encountered such a correction value for standard focal length lenses, including large format lenses. That's why the Summilux M 50mm/f1.4 2nd Generation has a special charm that is difficult to explain in words. As a result, I have kept this lens as my jewel for half a century. Ernst Leitz GMBh has been making this model for 30 years without changing it's basic lens design, and this fact is backed up by the unwavering confidence in this lens.
Judging from the point of view of recent demands, the only drawback of the Summilux M 50mm/f1.4 is its helicoidal structure. The typical value for standard lenses these days is around 45cm, but the shortest distance of Summilux M is 1.0m to match the Leica M model's rangefinder adaptation. To solve this unavoidable problem, I decided to replace the Summilux lens with a standard SLR lens case equipped with a Hexanon 52mm/fl.7, which had mold in void, on the Sony E mount.
This time's work is porting from SONY E to GFX mount. As a lucky tip, Pixco has supplied us with an M65-GFX adapter compatible with the helicoid-equipped Summilux 50 at a reasonable price, bingo!!
Preliminary experiments to adapt it to the 44x33 large format have proven this lens' performance, although if you look closely you can see very slight vignetting in the corners. After that, we made final adjustments to the infinite position setting using the full length of the helicoid, and spent several days rebuilding and rehabilitating it. My gem “Summilux” will soon survive in large format.