These lenses are just great. Designers have to make so many compromises with short SLR lens ( even the common 50 is tough to make: to get past the mirror requires a retro-focus design ! ). A plain old 35 mm lens is hard for an SLR or a RFDR. But the relative freedom of an 80 to 100 lens makes optical wonders possible.
Seemingly modest lenses ( 90/4 Elmar, for example ) are beautiful.
David's recycled Ektar is one of the most sublime examples of a good idea I've seen in a while.
And, having gone through the Book of Rare and Esoteric lenses in my chequered career ( Thambars and Beyond ) the prettiest, most useful, and wonderful portrait lenses are really pretty common.
The 105/2.5 Nikkor ( in either version ) has no shortcomings, and is about as common as dirt on Ebay. For a Leica, the 90 Summicron, Elmarit, and Elmar (made from the '50s through the '80s) are easy to find and easy to pay for.
The M42 lenses are wonderful, starting with the 135 Sonnar. The Takumar 85 and 105 are harder to find today, but not rare-collectable-unobtainable. And the all-time value for money champion ? The Jupiter 9 ( 85/2 ) is a sweet, sweet lens. Another classic Sonnar design.
Olympus/Minolta/Konica, everybody made a masterpiece in this length. The Cosina 'voigtlander' lenses seem to be quite fine, and why not ?
The Canon 85/1.8 is worthy of a book all its own.
So shoot up and be happy. This is a great topic because there IS no bad news here ! Well, I've found a few stinkers, but you'd have to go out of your way to find them, and I'll just let them go unmentioned.
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