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Cosina 55mm F1.2

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5 30,806 Sun September 1, 2019
Recommended By Average Price Average User Rating
100% of reviewers $335.00 9.00

Cosina 55mm, f/1.2
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amateur dirt farmer

Registered: December, 2014
Location: probably out in a field somewhere...
Posts: 22,800
Lens Review Date: September 1, 2019 I can recommend this lens: Yes | Price: $175.00 | Rating: 9 

Pros: color, clarity, sharpness, rendering, quality-feel
Cons: less-than-modern coatings, long-ish MFD, occasional CA
Sharpness: 9    Aberrations: 8    Bokeh: 10    Handling: 9    Value: 10    Camera Used: K-3   

where did that month go?

for the August Single In Challenge, I used a recently-arrived Cosina 55mm f1.2, purchased at what can only be considered a fire-sale price from another PF member...

my copy is mint, barely-used (if at all), with no marks on the glass, body, or mount - both the focus and aperture rings feel factory fresh...

this is a mostly-metal classic, 58mm filter ring, and front-heavy - you can feel the massive amount of glass contained here...

about mid-month, I switched to a deeper hood to help with the loss of contrast in strong daylight - it helped, but there were still shots that you knew a modern multi-coating would have helped even more...

this lens has it all in spades: smooth bokeh, lovely deep colors, and a degree of sharpness that helped me forget it large minimum-focusing-distance of 2' - if I wanted a closer composition, the lens is sharp enough to simply enable me to crop...

any negatives? other than the lack of modern coatings, a little on the large size, and the MFD, there are really no downsides to this lens... stop it down to f2.8 or beyond and it's as sharp as another lens in your bag, but it's the big aperture that you bought it for, right?

at f1.2, the entire world changes - the amount of concentration to nail the shot is immense and when you do get the shot, you'll dance inside... really, you will...

recommended? yes, but you may have to set some limits as far as price and just watch for a bargain...

compared to the Porst 55mm 1.2, the Cosina is an easier lens to live with, day in and day out - the Porst is a little smaller, renders differently, but has similar bokeh to the Cosina...

some of my favorites so far:

fresh by Pepperberry Farm, on Flickr

zinnia by Pepperberry Farm, on Flickr

Sol by Pepperberry Farm, on Flickr

peppers by Pepperberry Farm, on Flickr

barn & blue sky by Pepperberry Farm, on Flickr

and the rest of my album:
Site Supporter

Registered: April, 2015
Location: Wisconsin, USA
Posts: 2,707
Lens Review Date: April 12, 2016 I can recommend this lens: Yes | Price: $400.00 | Rating: 9 

Pros: Bokeh, Sharpness, true-to-life colors
Cons: Contrast
Sharpness: 9    Aberrations: 9    Bokeh: 9    Handling: 10    Value: 9    Camera Used: K3ii   

This is my favorite 50mm-ish K mount lens.

I just spent two days comparing this lens against my Voightlander 58mm f/1.4, Zeiss ZK 50mm f/1.4, and Pentax 50mm f/1.7 lenses. Other than having ever so slightly lower contrast (which I easily tweak in post) this Cosina lens clearly beat these other 3 lenses in terms of: sharpness, bokeh and true to life colors!

UPDATE: I just finished testing this lens against my Revuenon 55mm f/1.2 lens. Wide open and up to f/2, I prefer the bokeh from the Revuenon. Why? The Cosina can produce distracting double lines in out of focus areas.

Registered: August, 2011
Location: Langwarrin Australia
Posts: 382
Lens Review Date: March 24, 2012 I can recommend this lens: Yes | Price: $375.00 | Rating: 9 

Pros: Beautiful Bokeh, Sharp Stopped Down, f1.2
Cons: Needs a stop indent between f1.2 & f2
Sharpness: 9    Aberrations: 8    Bokeh: 10    Handling: 9    Value: 10   

This lens you buy for its bokeh, its backgrounds like an impressionist painting. Like most fast fifties when its stopped down its very,very sharp especially in the centre. Where else could you find a quality f1.2 for under $400.
Veteran Member

Registered: October, 2010
Location: Hong Kong
Posts: 327
Lens Review Date: March 16, 2012 I can recommend this lens: Yes | Price: $350.00 | Rating: 9 

Pros: beautiful bokeh @ f1.2, sharp when stopped down
Cons: prone to flare, can lack constrast, min focus distance
Sharpness: 8    Aberrations: 7    Bokeh: 10    Handling: 9    Value: 9   

extremely fun lens to use, usually leave it at f1.2 and use live view + info button to get things in focus, bokeh in my opinion is better than the A 50 1.2 / K 501.2, although not as sharp as them at f1.2 (but extremely dreamy images which is the effect i'm after!)

down side is it really needs a hood (i used a generic 58mm tele hood) to improve contrast and really need to protect the front element which is quite vulnerable, min focus distance is a bit longer than i liked, but i've been able to use it with a raynox and had some good results

stopped down it is excellent, but i tend not to use this lens past f1.2 anyway

highly recommend you get it if you have spare cash and want to explore some more creative photos

also you can use this with a 58 -> 49 step down ring if you have 49mm filters, there is no vignetting from my use so far on aps-c

Registered: January, 2009
Location: East Bay Area, CA
Posts: 6,273

8 users found this helpful
Lens Review Date: December 6, 2010 I can recommend this lens: Yes | Price: $375.00 | Rating: 9 

Pros: artistic bokeh, sharp when stopped down
Cons: slightly gritty focus ring, needs a detent between 1.2 and 2.0
Sharpness: 8    Aberrations: 9    Bokeh: 10    Handling: 9    Value: 9   

This is my favorite lens for artistic bokeh. Under the right conditions, it can produce backgrounds that resemble brush strokes in a painting. This is not a smooth or creamy boken as you may get from longer FLs, so if that is what you need, this may not be the best lens. BUT, when you need to make your close-up subject pop but keep some lines brewing in the background to tie it all together, this lens performs beautifully! It does best when the OOF background is far away and contains a mix of light and shadow, IMO. It also does the OOF circular highlights effect really well when used wide open (ie, holiday lights, etc). Just experiment a bit and you will no doubt fall in love with the lens.

I must confess, although this lens also works as a really sharp portrait or landscape lens when stopped down, I almost never turn the aperture ring beyond f/1.2, but I often rest it halfway between 1.2 and 2.0. Instead, I keep an M-50/1.7 in my bag when i want a sharp landscape. Who knows, maybe one day I will try the Cosina for landscapes too and edit this review, lol.

And if I really had to reach for a way to improve on the lens, I would want to be able to focus closer to my subject, which would be useful when shooting very small objects like tiny flowers.

Be aware that wide open (f/1.2) this lens is not nearly as sharp as at f/4, that's a fact of physics, but if you want the painterly effect, you may not be looking for absolute sharpness anyhow.

I did find the focus ring to become gritty/sandy-feeling after awhile, but this does not impact the accuracy of my focusing. I will probably open it up and relube soon.

Also, you must find a good hood for this baby or you will get flaring. I use a large 67mm collapsible rubber hood with a 58mm to 67mm step up ring.

This lens has a cult following and some amazing photos in this thread:
Definitely check it out!

here are a few samples:

stopped down to ~2.8

wide open

wide open
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