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Sigma YS / Spiratone 135mm F1.8

Reviews Views Date of last review
2 32,650 Fri November 27, 2015
Recommended By Average Price Average User Rating
100% of reviewers $200.00 9.50
Sigma YS / Spiratone 135mm F1.8

Sold in several variations under multiple brand names, this lens is about 3.5" across the front and about the same in length not counting the swappable YS (a sigma developed swappable mount derived from t-mount) adapter. It is as heavy as one would expect given the size of the glass.
DSG wrote in this thread:
"There were at least four different optical designs employed in all the various 135mm f1.8 lenses produced before the Pentax SMC-A (135mm f1.8).
Soligor used a simple optical design of 5 elements in 3 groups to produce their unique (as far as I am currently aware) version.
Mitake used an optical design of 5 elements in 4 groups to produce the following optically identical but differently branded versions:
Spiratone Plura-Coat, Porst, Computar, Promura, Kenlock, Formula 5, Eyemik, Apollo, Ultra-Unitor, Accura, Varo, Vivitar and Weltblick. (there may be even more brands that I don't know about yet).
An unknown manufacturer (possibly either Goyo optical (owner of Sun optical since 1976 onwards), Yoshida industries (Owner of the Raynox brand), Tomioka industries or one its subsiduaries, Tokina, or some other Japanese company yet to be discovered) employed a slightly more complex design of 6 elements in 4 groups to produce the following optically indentical but differently branded versions:
Spiratone (the normal version), Polaris, Raynox Polaris, Carena, Beroflex and Samigon. (again, there may be even more brands that I don't know about yet).
All the above 135mm f1.8 lenses have an 82mm filter thread, weigh between 1-1.2kg and have an MFD of about 6 feet (1.83m).
Sigma used a more complex Sonnar design, of 6 elements in 5 groups, to produce the Sigmatel Multi-Scalematic and the optically identical Sigma XQ version. Compared to any of the 82mm filter thread versions mentioned above, Sigma's design allowed for a smaller physical size (a 77mm filter thread), a lighter weight (about 820g), a shorter MFD of about 4 foot 3 inches (1.33m), greater sharpness and much better control of CA."

Aperture settings go from f/1.8 to f/16, with half-stop detents starting at f/2; there is a large "M A" switch toward the rear after the lens narrows. Close focus goes to about 6'.
Mount Type: Third-party (adapter required)
Price History:

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New Member

Registered: June, 2015
Location: Bern
Posts: 1
Lens Review Date: November 27, 2015 I can recommend this lens: Yes | Price: $250.00 | Rating: 9 

Pros: Fast, sharp (also at 1.8), little CA, nice colors
Cons: Very heavy
Sharpness: 9    Aberrations: 9    Bokeh: 10    Handling: 7    Value: 10    Camera Used: Canon 5D Mk1   

Auto Admiral 1.8 / 135mm (1975)
My lens is branded as "ADMIRAL". This is the name of a companie in Switzerland, reseller for optical products.
I think it is the same product as the Spiratone. For photos like portraits, i can only recommend this lens.

@ 1,8

@ 1.8 (1200 ASA / Available Light)
Junior Member

Registered: August, 2009
Location: Lexington, KY
Posts: 29
Lens Review Date: December 25, 2010 I can recommend this lens: Yes | Price: $150.00 | Rating: 10 

Pros: Fast! Well built, adaptable YS mount
Cons: Tiny DOF shows any focus error, low contrast WO
Sharpness: 9    Aberrations: 9    Bokeh: 10    Handling: 7    Value: 10   

Over the past year, I saw plenty of these with various defects go for scary big prices... then came this pristine copy with an FL mount at a very reasonable price. The lens is actually a YS/T mount, so adapting it to anything is trivial; a minute after I got it, it was M42.

I had seen many reviews comment that this lens was really not very sharp, but my copy is acceptably sharp even wide open. I think the problem is that the tiniest little shift in subject distance -- or error in focus screen/detector alignment -- is going to make a visible difference with this lens. Hit rate for truly sharp focus on a moving subject will be zero. Then again, this cheerleader sat still long enough for me to focus as intended:

The transition to out-of-focus is very smooth, so a minor focus error really does just make it look like the lens is a bit soft.

Oh yes, the lens is a bit soft -- not in terms of sharpness, but in terms of having low contrast. The backlighting didn't help either; this lens definitely is susceptible to a general drop in contrast as a result of flare. Thus, the above photo had a little level adjustment applied. This low contrast also will hurt the standard measured MTF numbers... but I don't care too much, as the detail is still there and can be enhanced by simple unsharp masking and/or tonal remapping.

Bokeh? Generally as nice as you'd expect from a 135mm f/1.8, very easily providing a truly smooth background for things like portraits. Here's an evil example with resizing as the only PP:

The LED Christmas tree lights incorporate lenses, which explains the wild variety of PSF structures seen. The yellow disc to the right is typical of how a real point source is imaged, just plain discs with a slightly soft edge and very little "cat's eye" vignetting (on an APS-C camera). Note the smoothness of the OOF chair, etc. There is pretty strong bokeh CA, but that isn't unusual in lenses with better-than-average smoothness in their bokeh, and it isn't likely to be obvious in a portrait unless the subject is a zebra.

Build quality? It doesn't feel like a consumer lens. It feels more like something made for industrial uses: very solid, but intentionally a little coarse. The flare issue probably comes from the shiny metal interior of the lens barrel; I don't know why they didn't use a little black paint.

Overall, I think this lens is a 10. However, this is a special-purpose lens for people willing and able to focus very carefully -- probably only effective using magnified live view. As a general-purpose "fast 135mm" this would be more like a 7 and you'd be much better off getting the f/2.5 135mm Takumar. The Tak is cheaper, relatively small and easier to hand hold, nearly as fast, and far less touchy to focus.
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