Focusing ring index

Two different types of Summilux 50/1,4 have fundamental change in helicoid construction, the newer model shown left side has steeper angle of spiral pitch, probably because of quick focusing character. The distance between 5 m to infinity positions are changed into narrower for the silver brass barrel model. The lens element designs are the same though coating methods are different resulting more bewitching color resolution for new model.
Exactly the same arrangement by Minolta company is observed on New MD 28/2 model, so there is some inconvenience to guess a focusing distance and set on focusing ring because of no identification letters on narrow distance. This is why I made up my mind to use it on Canon EOS 7D with through the lens(TTL) focusing method instead of M9 with visual estimation. Of course MD 28mm is used as 35mm view angle lens on APS-C imaging format. Quicker focusing manner is always better than conventional slow ritual? I don't think so, I prefer stable and steady focusing process to restless procedure and some traditional and delightful attitude while shooting might suit Leica range finder model?