Originally posted by IgorZ I am tempted. But then when I start looking at them I get really tempted to get a Biotar. These guys get up to 17 blades...
I remember reading comparisons between Helios 40 and biotar 75 f1.5 and from what I remember, the Biotar provided more swirl. But reviews on Russian websites seem to suggest that Helios 44 does more swirling than Biotar 58mm...
I own no Biotars, just russian knock-offs.
Original Zeiss Biotar lenses are collector's items, too expensive for my taste, considering that from a photographic point of view there is no big difference from their russian counterparts.
The Helios 40 1.5/85mm is a great lens for full frame, but I had no time to test it properly. Just a first impression.
I have no experience with the 40-2, of course it has a much better coating, but I believe that vintage russian lenses had better QC and often had much better build. Not all of them, but my Helios 40 has a very robust barrel construction, and has resisted the injuries of time pretty well.
A tad too heavy, though
The various Helios 44 are rather different one from the other. The K44 is the most practical, but the best one is the original 44, followed by the 44-2.
Unfortunately my old 44, with click-less diaphragm and plenty of diaphragm leaves, can't reach infinity. I tried with a M39toM42 ring, plus a Pentax adapter ring (to PK); the register should be ok but it's not.
I have to try if the helicoid has enough room for registration, other way I must mill the base of the lens.
The 85mm works fine, instead. The seller from Ukraine sent me the lens with the M39 ring on, and when I tried it on a good PK adapter the infinity was spot on.
Apart from the eventual need for focus adjustment, the two M39 (or, more correctly, LTM) versions are the best, IMHO.
Both are nicely made, and the optical signature is great.
If you are not a collector, and the lens you want to buy is meant as a "user" one, I wouldn't invest in an original Biotar
Cheers
Paolo