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Cosina MC Cosinon-T 135mm 1:3.5

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6 17,986 Sun August 30, 2020
Recommended By Average Price Average User Rating
100% of reviewers $13.33 8.50
Cosina MC Cosinon-T 135mm 1:3.5

Cosina MC Cosinon-T 135mm 1:3.5
Cosina MC Cosinon-T 135mm 1:3.5

Manual prime lens. Multicoated.
Built-in hood.
Focal length: 135mm
Max length: 97mm + mount (hood extented)
Max diameter: 62,5mm
Weight: ~280g
Aperture: f/3.5-f/22, 6 blades
Min. focus distance: ~1.45m
Filter diameter: 49mm
All metal construction.
Mount Type:
Price History:

Add Review of Cosina MC Cosinon-T 135mm 1:3.5
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New Member

Registered: November, 2013
Posts: 8
Lens Review Date: August 30, 2020 I can recommend this lens: Yes | Price: $20.00 | Rating: 9 

Pros: sharp lens, nice colors, good small lens
Cons: on big posters visble small CA's wide open, especially in the corners
Sharpness: 9    Aberrations: 8    Bokeh: 9    Handling: 8    Value: 10    Camera Used: k-5, k 200d, Fuji x-t100   

Cosinon Lenses are sold under different labels as Exakta, Carenar, Via Brillant, Porst, Revuenon, inspite of 2.8/135 declaration, sometimes. It hat f 3.5 wide open.

This is the newer version with still better multi coating.

Qptical qualities in 4/4 element construction are really excellent for this low price.

This edition is wide open suitable for stars photography

++ sharpness, colors, and contrast are very good.

+/++ some few flare against the light and some few CAs.

Highly recommended at this low price 8.5 points

Registered: May, 2014
Location: Linz
Posts: 1,487
Lens Review Date: July 4, 2018 I can recommend this lens: Yes | Price: $10.00 | Rating: 8 

Pros: Small, light, sharp, buildquality
Cons: Black anodised mount, CAs
Sharpness: 9    Aberrations: 7    Bokeh: 8    Handling: 8    Value: 10    Camera Used: K-3   

I own this lens for about a year now and I couldn't be happier with it. It's build quality is good and despite beeing a metal lens it's still small and light enough to permanently stay in your camera bag.
As a matter of fact it is very often the only lens I take with me in addition to my walkaround lens (Pentax-F 35-70mm) when hiking or climbing because it doesn't add much to the backpack.

The built-in lens hood is nice to have and in some situations it really helps but it is generally too short especially for aps-c cameras to have a strong impact on image quality.

There are some CAs visible especially wide open but they are manageable in post processing. Purple fringing can occur in high contrast situations like reflected sunlight from metal or water but it is usually easily dealt with in PP too.

Sharpness is useable wide open but for best performance stop down to f5.6 or f8. I often use f5.6 for people photography because in my opinion it is a good combination of sharpness and there is still enough subject isolation.

The focus throw is about 180 from infinity to MFD (1.5m or 5Ft) and allows precise focusing. The minimum focus distance of 1.5m is not that great but it's also pretty standard for a lens of that type.
Additionally is this lens sharp enough to use it in combination with extension tubes if you want to do close-up or macro work with it.

I only gave this lens a 8 for handling because I have 2 small issues with this lens.
1. The black anodised mount that prevents my camera to stop down the lens
2. Because of the big focus ring there is not enough space on the lens mantle for mounting the lens on the camera so you have to grab the focus ring or the aperture ring.

For the first problem I found two possible solutions: stick a small piece of aluminium foil between lens and camera when mounting or, if you want a permanent solution like me, sand down the black paint at the position where the camera checks for conductivity.
The second problem doesn't have a solution but merely the additional work of rechecking the aperture ring after mounting the lens if you have changed the aperture by accident since you used it last (Not a problem if you use the lens just once or twice a day, but if you change from and to this lens during an event you might not expect your lens settings to change)

All in all a lovely little lens I can fully recommend.

Train Station by Patrick Bittermann, auf Flickr

Macro picture with the help of extension tubes:
Dragonfly by Patrick Bittermann, auf Flickr
New Member

Registered: June, 2017
Posts: 6
Lens Review Date: September 11, 2017 I can recommend this lens: Yes | Price: $8.00 | Rating: 9 

Pros: light and beautiful finish
Cons: F3.5 - good for crop digital
Sharpness: 8    Aberrations: 8    Bokeh: 9    Handling: 10    Value: 10    Camera Used: P30 and M4/3 Lumix   

I have this in both the Cosina and Petri badging. I also have two SMC Pentax 135mm F3.5 to compare with.

There is little in it between them except the price. The finish on the Cosina/Petri is excellent - lots of beautifully smooth metal and a focus action like butter. They are tiny - slipping unobtrusively into the camera bag. The lens mount is solid and the aperture clicks into place so you can count the stops go by without taking the camera from you eyes.

Telephoto lens design for F3.5 was near optimal by the 1970s - since the classic zeiss 5-6 elements in 4-5 groups arrangement of lenses was off-patent. Large aperture lenses of that era sufferred CA at the edges - because coatings and aspheric elements either weren't invented or couldn't be afforded - so unless that F2.0 is crucial to you - save the cash and weight by buying the lower spec amateur lenses.

Picture quality on all 4 135mm F3.5's exceeds all my 135mm F2.8s intil they get stopped down to F8.

On a crop camera the DOF at F3.5 is suitably shallow to isolate the subject from backgrounds - so much so that you have to be spot on with the focus. Edge sharpness doesn't then matter. Remember that on an APS this is a 200mm and with M4/3 this is a 270mm F3.5, so [1] buy a long "telephoto" lens hood for maximum contrast and [2] use the ASA/ISO controls to keep the shutter speed at ≥1/300th to minimise blur. Sharp with a bit of grain/noise is always better than soft and blurred!

In the light, for landscapes, go for about f8 and the IQ peaks on my M4/3. On a digital body - diffraction will lose contrast at small aperture sizes (F11 and up)

On a 35mm film camera a burst of fill in flash at 1/4 - 1/2 power does wonders for creating that extra "bite" of resolution in portraits with a 135mm that you might have had to sacrifice at slow shutter speeds. It also adds the "catchlight" to the eyes. A pocket size slave flash (Ebay has some cute Kenro ones now at only GBP 2.99 - powered by 2xAA batteries that can also distinguish pre-flash) at 45deg of axis adds the professional portrait touch that fits in a pocket at pocket-money prices.

The colour balance looks great for people and places - so I don't have to make unexpected photoshop corrections. If you insist on looking at 100% pixel size I daresay there will be something not to like - but for on-screen viewing or 10x8s I am very satisfied.

I paid GBP 7 (about USD 8-9) for both my copies of this lens in 2017. At this price it is a steal for a K-mount user. SMC Pentax 135mm F3.5s are costing 4 times that in 2017.

As this is an "amateur" lens expect it to have been used lightly and often look like new. My two are almost mint. But beware fungus after it has lain in the back of a drawer through the 1990's as the previous owner fell for the charms of a zoom lens - then later for a digital camera - before finally passing it on to Ebay decades later! They were clearly popular - with 2 on sale on UK Ebay just now you should be able to track one down (one Petri badged version is at just GBP 5.99).

Now if the prices surge on Ebay I have only myself to blame!

Registered: May, 2015
Location: Hampshire
Posts: 891
Lens Review Date: May 12, 2016 I can recommend this lens: Yes | Price: $15.00 | Rating: 9 

Pros: Quite petite, good at F3.5
Cons: Black anodised mount.
Sharpness: 8    Aberrations: 8    Bokeh: 8    Handling: 8    Value: 9    Camera Used: K-5   

Beware the black anodised lens mount. If you buy one with the surface that mates to your camera mount contacts painted or anodised black, it will not stop down from F3.5 in manual mode on the K-5. . Fine with an old film camera that doesn't have the contacts and for some reason also fine on my K20D. This is the third or fourth lens I have had with this so it's not uncommon.
You may need to slip some silvered paper between the lens and contacts or rub off a patch that lines up with the contact that matters till a bit of bare metal shows.
This problem has been highlighted in the forums a fair bit and diagrams and photos of the pin in question are there too.. It also reduced the handling down a point or two for me.

I got this lens after bidding for a Cosina camera that was for some reason fitted with a Pentax-F 35-70mm zoom! as well as this and a Cosina 50mm F2 lens in the bundle. It was the AF zoom I really wanted but after delivery found that the zoom optics were bad with haze and maybe fungus too, likewise the 50mm.

This lens looked in very good condition though and I was surprised at how well it provided images at F3.5, probably better than any of the other cheap 135mm's I have, including a Super Takumar 135mm F3.5.

Don't turn your nose up at this if you are offered one, it's likely to be rather cheap, quite small and it's shorter than my Sigma 50mm macro at full extension. Colours seem quite good too. The only downside is the mount problem really.

Registered: March, 2013
Posts: 360
Lens Review Date: March 23, 2013 I can recommend this lens: Yes | Price: $15.00 | Rating: 8 

Pros: Size, Weight, Sharpness
Cons: Slow, Focus ring not smooth enough
Sharpness: 9    Aberrations: 8    Bokeh: 8    Handling: 7    Value: 9   

Size, weight and optical quality of this lens is almost identical as Pentax M 135 f/3.5. Mechanicly is not so good as Pentax M 135. Sharp wide open. Most compact 135 lens on the market. Great price/performance ratio. At 3.5 is sharper than many 135 f/2.8 lens at f/4. But it is a little bit slow, for a low light situations, for concerts as example needs ISO 1600 or 3200.
Senior Member

Registered: June, 2009
Location: Finland, Kotka
Posts: 169
Lens Review Date: March 18, 2012 I can recommend this lens: Yes | Price: $12.00 | Rating: 8 

Pros: Quite sharp even at wide open
Cons: Manual, slow
Sharpness: 8    Aberrations: 8    Handling: 9    Value: 9   

I bought this lens 3 weeks ago. Before that I tried to search some info about it, but allmost zero results.
I added this lens to database after I got it. And now I have to make first review too

I'm not good tester about optics, so I give you some samples, all shot with K200D handheld:

Outdoor picture, ISO 400 f 8-16 (cant remember), little cropped and sharpened.

Indoor, ISO 100, f 8 or 11, no sharpening

Indoor, 100% crop from previous

Indoor, wideopen 100% crop, no sharpening, little CA when white with dark backround

Overal great little tele.
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