Yashica Auto Yashinon DX 50mm f1.7 – Legacy 50mm. Which one is the best? Part 1
I am preparing for a long time to put in test as many 50mm MF lenses as I would be able to collect. Now, I have some 20 pieces, including 2 more respected (more expensive at least) Canon FDn 50 f1.2 and Leica Summicron R 50 f2.
I decided to start slowly to publish some results, and will add other lenses as time allows me to.
First lens for my small review is not so well known Yashica AutoYashinon-DX 50mm f1.7 In M42 mount.
Here is the lens mounted on NEX 7.
It is quite hard to find informations about this lens on the web, and it is not 100% clear, does this lens contain Thorium (Radioactive) element or not.
From what I was able to find, it seems that DX version of this lens is not radioactive, while DS version is. Some reviews however say it contains Thorium.
Lens is approx. 42mm long and with M42 adapter for the NEX it has around 70mm. During focusing it extends about 10mm, but the front element does not rotate.
Build quality is outstanding and after many years, focusing ring is still greatly smooth and precise. Full focus thread takes around 250°. It takes 52mm filters and weight around 230g. There is no multi coating on this lens.
Minimum focus distance is around 50 cm. Which is rather long in its class.
Lens has following aperture stops: 1.7, 2, 2.8, 4, 5.6, 8, 11, and 16.
Price of my sample that isn’t in the best cosmetic condition, but with no cleaning marks or fungus on the optics and fully functional was 50 USD at the local shop, but I believe it could be found for less on eBay.
Here are test shots at all apertures. Focusing was at the dolls left eye. Shot from tripod with remote, ISO 100, NEX 7, RAW developed in LR 3.6 with standard settings, exported for downsizing in Photoshop. No other corrections applied.
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| Sony NEX 7 + Yasica Auto Yashinon-DX 50mm f1.7 at 1.7 |
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| Sony NEX 7 + Yasica Auto Yashinon-DX 50mm f1.7 at 2 |
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| Sony NEX 7 + Yasica Auto Yashinon-DX 50mm f1.7 at 2.8 |
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| Sony NEX 7 + Yasica Auto Yashinon-DX 50mm f1.7 at 4 |
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| Sony NEX 7 + Yasica Auto Yashinon-DX 50mm f1.7 at 5.6 |
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| Sony NEX 7 + Yasica Auto Yashinon-DX 50mm f1.7at 8 |
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| Sony NEX 7 + Yasica Auto Yashinon-DX 50mm f1.7 at 11 |
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| Sony NEX 7 + Yasica Auto Yashinon-DX 50mm f1.7 at 16 |
Lens is just slightly softer at f1.7 in the center, while it shows very good sharpness in the center from f2.8. At f5.6 and f8 it is very sharp across the frame.
I also like a rather natural colors it produce, and therefore I believe there is no Thorium element, as otherwise, considering its age, it would probably be yellowish.
Bokeh looks very nice to me. It is subjective of course, but it looks quite smooth.
At f1.7 it is smooth as a butter…
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| Sony NEX-5n + Yasica Auto Yashinon-DX 50mm f1.7 at 1.7 |
But even at f5.6 and more contrastingly lit background it is pleasant to my eye.
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| Sony NEX-5n + Yasica Auto Yashinon-DX 50mm f1.7 at 5.6 |
All in all, for bellow 50 USD (adapter cost 4.99 USD), I think it won’t be easy to beat this Yashinon 50mm as the classic portraiture lens on APS-C. But there are many contenders sitting on my shelf, ready to proof me being wrong.
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| Sony NEX-5n + Yasica Auto Yashinon-DX 50mm f1.7 at 1.7 2000 ISO |
At f1.7mm DOF is so thin, as you can see, that it leaves only one eye in focus, even if there is only few mm difference in the focus plane.
Here are couple of night shots with the lens, where flare doesn’t seems to be an issue, even if the lens doesn’t have Multicoating.
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| Sony NEX-5n + Yasica Auto Yashinon-DX 50mm f1.7 at 4 |
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| Sony NEX-5n + Yasica Auto Yashinon-DX 50mm f1.7 at 8 |
Here are crops from ISO 12333. Please note, that due to the lens sample, alignment imperfection, or adapter imperfection, results in the corners could be compromised. Rather than judging something that looks like lens mis-alignment, look for the CA and center resolution. Distance from the chart was 100 cm. Chart is A3 size.
As you might see from those 100% crops, the biggest problem seems to be wide open at the left side. Otherwise, CA is very low at any aperture and vignetting can cause the problems up to f4. Center resolution is good wide open and lens best performance is between 5.6 and 8.
Let’s see, how it look on a real subject at the distance of 10m. (Not perfect subject for center resolution, but I don’t have better, that I can shot repeatedly.)
Results are more even now, because the focus distance is not that critical as in a ISO 12333 test. This results could be taken more objective, when it comes to the corner performance.
There is slight barrel distortion, but nothing I would consider as a serious problem.
Conclusion…
Yasica Auto Yashinon-DX 50mm f1.7 is very good 50mm lens. I am not willing to establish any rating system, as they are usually too subjective.
Lens is very well built, not too bulky or big (adapter makes it bigger but still acceptable). It is joy to use its focus ring for manual focusing. Lack of CA and very good overall sharpness from f2.8, are pleasing, as is the nice neutral color rendition and good contrast.
Considering its low price and the fact that over 30 years old lens doesn’t disappoint on todays high resolution 24 mpx APS-C sensor of NEX 7, I can only recommend it.
C/Y Zeiss 50mm f1.7 might be nice addition too. 🙂 And usually its cheap.
And you might compare all to 35-70mm f4 Leica R set at 50mm (I bet it will be sharpest).
Yea and I kinda like 50mm f1.2 AiS, its not like Noct-Nikkor but still nice.
… and also have this one… It’s been neglected for a while, but I will give it a second chance.
Keep up the great Work.
I got this lens a few months ago and is excellent using on the NEX7, contrast is excellent and very sharp, although don’t really like the adapter because adheres more volume, the construction is very strong, solid and is very easy to focus quickly turning the ring when I walk by street.
Greetings friend, I really liked your article.
Great review. I use this lens on film for about a year now along with its DS and DS-M siblings, so I can only speak about the overall feel of this lens, as I am not into pixel-peeping. They all give very similar results and in my opinion they are very underrated and can be found pretty cheap on eBay. They are easily comparable to my standard Takumars (even the 1.4/50) for a fraction of the price. The DX line has the best construction (again comparable to the Takumars, incl. smoothness of focusing ring after all these years). The only problem is that the DX lenses can hit the mirror of many DSLRs (and many film SLRs as well) when focused to infinity (not a problem with DS and DSM lenses). Not owning a Leica lens of any sort, the 1.7 Yashinons have frequently fooled me into believing that many great shots on flickr were made with Leitz lenses, when in fact they were made with a Yashinon. By the way, great photos of the Prague Castle. I lived in Prague for 8 years, it was the best time of my life.
Thanks for review, it was excellent and very informative.
thank you 🙂
Thank you for the review. Very well done!
I have a copy of this lens and have been amazed by its quality. First I found it a bit soft compared to modern lenses and somewhat of an ugly duckling but as I started using it for videos, it’s shown its worth. Amazing image quality is more than just simple sharpness.
I think many places report that it is radio active. Whether is thorium or not, I’m not sure. From what I see, the glass elements have that yellow tint, though the images seem fine. Either way, I’d advise against holding it to sleep.
Hi,
congrats on your lens. It has lanthanum in the optics, but don’t worry much about radiation. The simple paper bag or anything similar will almost entirely block the radiation, so that you can even keep it in the sleeping room 🙂 Use simple UV lamp (black light) to reduce yellowness and improve contrast and resolution.
Cheers, Viktor
Thanks for your post about this and other classic 50m, very useful. I have the DS version and I can confirm is radioactive. When I first get it, it had a thick yellow tint, very difficult to fix in post. After some days of natural light, the yellow tint dissapearead, except a little bit on the lens that does not affect the picture and may be due to the coating.