It is probably worth repeating a few words of advice I gave in the previous review involving a Russian lens. Just skip ahead if you’ve read them already.
Disclaimer
First a bit of advice. A review is always speaking of a single lens, really, given quality control issues, the previous life accidents in a pre-owned lens and so on.
But with the so called Russian lenses this advice assumes an entirely new extent. First of all because of the extremely poor quality control they had in the Soviet factories – there is the legend that lenses made on mondays were of lesser quality, because of the hangover from the previous weekend… Then because, especially the rangefinder variants of those lenses, required some adjustment to make them perfectly compatible with Leica-like bodies. This is not a concern to the mirrorless user, but this adjustments, unfortunately, were often made by the unskilled owners themselves, with the results you can expect.
On the bright side, though, if you find a sample in good shape, maybe buying from a reputable seller – or, given the low cost, buying and selling until you find the right one – you will be often in for a treat. That said, with a bit of attention to the pictures (I was buying from an auction site) and searching for the older ones – supposedly better made (the first two numbers of the serial number indicate the year of production) – I was able to find a few Russian lenses without incurring in lemons.
The review
The Jupiter-3 50mm f/1,5 is another Zeiss Sonnar clone, and its design originates in the ’30s. Small and compact, like many (all?) ex-USSR lenses mechanically is pretty poor. The focusing action is kinda gritty, the aperture is without clicks (a pain in the a** for photographers, but pretty handy for videographers). A far cry compared even to the lesser Leica projects, but still with a better focusing action than last year Sigma 35mm f/2,8 for Nex!
It has an aperture mechanism similar to the one of the Jupiter-9, meaning that the iris will stay (almost) perfectly circular no matter what the aperture is. So at all the stops you will have a soft, smoooooooth bokeh graciously declining in the distance. Obviously closing the aperture will still increase the depth of field, but you will never see those horrible hexagon-shaped out of focus points. Being a 50, instead of a 85mm, obviously it will have more depth of field to begin with at any given aperture value. I’m getting the best bokeh at f/2, with less colored rings around the bright out of focus points.
This lens – or at least my sample – is a tad worse than the Jupiter-9 85mm. Worse, in this case, it means only that is not a spectacular bargain as far as price-quality is concerned. In fact this is a very sharp lens, just not so great like its cousin; more, nowadays its price is a tad steeper, but still accessible.
Like in the previous review, given the vast difference in quality you can find with these lenses, I will not show you test charts; it would be useless. That said, on the demanding sensor of the Sony Nex 7 it performed really well, especially if you, like me, will use it more for its impressionistic way of rendering a scene than for shooting ultra-sharp images. Color images are beautiful, but black and white pictures taken with the Jupiter-3 are simply jaw-dropping. They tend to exhibit a gorgeous scale of tonalities; this apparently is often the case with single coated lenses. That said, my sample however appears to be multi-coated, so I assume this “long gray scale rendering” depends more from the optical proprieties of the kind of glass used.
Given that this one was an even more appealing lens for Leica-owners, and so more samples have been subjected to surgery by inexpert hands to adjust the cam to Leica specs, I would strongly suggest to buy one from a reputable seller.*
Rating: 
*That said, I bought mine on eBay and I didn’t have a problem.
