Nikkor-S 55mm f/1.2 Experiences?

ferider said:
Nowadays, quite a rare design for a fast normal, a rear-extended Planar ...
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This design is absolutely not rare. To the contrary—in those days everybody designed their fast (1:1.4, 1:1.2) standard lenses (50 - 58 mm) in exactly the same way: Double-Gauss (= 'Planar' in Zeiss speak) with seven elements in five groups.

Slower standard lenses (1:2, 1:1.8, 1:1.7) usually were, and often still are, six elements in four or five groups. For the faster designs, the rear element was split into two separate elements, for a total of seven elements.



ferider said:
... (where the typical more modern 50/1.2—Zuiko, Nikkor, etc.—all have two more air/glass interfaces).
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In the '60s and early '70s, every lens maker grouped the seven elements into five groups, using two cemented groups. With the upcoming multi-layer coatings, within a few years during the mid-'70s all of them switched from the then-usual 7/5 design to the more modern 7/6 design which provides two additional degrees of freedom and is easier to manufacture but causes more internal flare which however is kept under control through the improved coatings.
 
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