Does anyone know about this lens? [Exaktar Auto 50mm f/1.7]

MDPI · Joined: 15 Apr 2024 Posts: 6

Hi,

First time posting here:)

I am having difficulty finding information about this lens.
The lens has a native M42 mount with an attached adapter for Exakta mount, which can be removed.
From my Google search, I gathered that this lens was likely made in Japan by Cosina for Exakta Twin TL.
During my search, I came across the Exaktar 55mm F1.4, 55mm F1.7, and 50mm F1.8 variations. However, besides a post from a Japanese blogger, a M42 mount lens database site (with limited information), and one Flickr user who uses this lens, I could not find any additional information about this variation.

At this point, I think the lack of information on the Internet is due to the fact that this lens is either very rare or not worth mentioning due to its abundance.

Any help will be greatly appreciated.
Thank you!

Below are the links to the three sources where I was able to find information about this lens.
https://m42lens.com/m42-lens-database/1368-exaktar-auto-50mm-f-1-7-16
http://blog.livedoor.jp/toshioimawaka/archives/4720607.html
https://www.flickr.com/photos/lordakner/14219156571

Image of the Lens:

55 · Expire: 2022-06-15

MDPI · Joined: 15 Apr 2024 Posts: 6

Thank you so much!
I was trying so hard to show the images for past 30 min haha

55 · Expire: 2022-06-15

Alun Thomas · Joined: 20 Aug 2018 Posts: 631 Location: New Zealand

At first glance it appears to be a Cosina made lens just going off the font on the name ring. If you post more photos of the focus ring markings and the mount we can get a clearer idea. The Twin TL camera was made in two versions, the first version used the Exakta Real mount before the second version appeared with an M42 mount. The camera itself ws a version of Cosinas Hi-Lite camera, which was very similar to the Ricoh TLS. Following that some subsequent Exakta M42 mount cameras (TL-500, TL-1000, FE-2000) were made by Petri, these came with either a Sankor 55mm F/1.4 or a Petri 55mm F/1.8 or 1.7. Following that they moved to the popular Pentax K open mount with other models. There was also at one point a version of a late model Topcon camera (made by Cimko from memory) using their version of the original Exakta mount with the Topcon alterations.

MDPI · Joined: 15 Apr 2024 Posts: 6

Thank you for the reply.

The lens I have look exactly same as the one in the m42 lens database site.

https://m42lens.com/m42-lens-database/1368-exaktar-auto-50mm-f-1-7-16

alex_d · Joined: 19 Jan 2019 Posts: 339

thats a very rare lens

D1N0 · Joined: 07 Aug 2012 Posts: 2504

Pretty sure that is a Cosina made lens akin to the Auto Cosinon 50mm F=1.7. One of the several rebranded Cosina made camera or store brands. You'll also find it as Porst.

MDPI · Joined: 15 Apr 2024 Posts: 6

MDPI · Joined: 15 Apr 2024 Posts: 6

georgegrant · Joined: 25 Jan 2021 Posts: 18 Location: Chongqing, China

D1N0 · Joined: 07 Aug 2012 Posts: 2504

Chinon never made lenses, just Cameras. They used third party for their lenses.

BrianSVP · Joined: 09 Jun 2023 Posts: 303 Location: Philadelphia

Do you have a source for this? I've seen this contention before, but I also have seen some Chinon lenses that AFAIK don't appear to have any twins except for known Chinon licensees (GAF, Revue, etc.) and Chinon-owned brands (Late period Alpa).

They were a sister-company and later a fully-owned subsidiary of Kodak, so they presumably had access to some excellent optical manufacturing.

D1N0 · Joined: 07 Aug 2012 Posts: 2504

They worked with Cosina, Tamron, Tomioka, Sun Optics for zooms probably also Tokina.

http://camera-wiki.org/wiki/Chinon#35mm_Camera_Lenses

They did make lenses, but not for 35mm. For 8mm film and later Video.

BrianSVP · Joined: 09 Jun 2023 Posts: 303 Location: Philadelphia

That Wiki link simply makes the unsourced statement that they worked with other manufacturers, not that they never manufactured any of their own. In fact, the only citation given on that page is a link to a post here by Pancolart that's just a list of lenses. Four of them are indicated to be Tomiokas. Of these, three have "Tomioka" on the name ring itself, so it's pretty clear that at least the optics were made on them in their earliest versions. As discussed in other threads here, the later iterations of the 1.4 may or may not have been sourced from Tomioka, and the attribution of the 55mm f/1.7 as a Tomioka is probably wrong.

The only other lenses in Pancolart's list that are securely identified by him as manufactured by someone else are the 17mm, 300mm, and 500mm which are twins of ubiquitous Tokinas. You can add onto this some of the tapered barrel ones that are twins to some Tamrons. AFAIK, there are one or two zooms securely identified as Cima/Cimko. That accounts for the manufacturers listed in the camera-wiki article, but leaves a whole bunch of lenses whose manufacturer is unaccounted-for, including several of their primes. I'm not familiar with the Sun stuff, but you yourself says it's restricted to zooms.

To me, then, there's hardly a basis to make such a blanket statement that they made no 35mm lenses and sounds a lot more like typical "internet wisdom" that's conjecture piled on conjecture. Lots of brands both built their own lenses and farmed out work to other manufacturers. Heck, Ricoh-Pentax still has Tamron and Tokina build some of their lenses.

I can't speak to who made the optics, but I can tell by first-hand having worked on many Chinon lenses that there are certain mechanical design characteristics, of several lenses, particularly in the aperture mechanism, that are absolutely 100% unique to the brand and its sub-brands/licensed rebadgers. I can also say that some of the optical designs, (e.g. their 45mm pancake and the Chinon/Alpa 55/1.7 macro) don't show up anywhere else except as Chinons or as Chinon-owned/sublicensed brands. Could their manufacture have been farmed out to other companies? Sure, I suppose, but any attribution is pure speculation.

I'm still unconvinced.

D1N0 · Joined: 07 Aug 2012 Posts: 2504

It is not my job to convince you of anything so I will leave it here

georgegrant · Joined: 25 Jan 2021 Posts: 18 Location: Chongqing, China

D1N0 · Joined: 07 Aug 2012 Posts: 2504

... source is not good but I have an anecdote and sources that are good but I will not bother to name them....

iso rivolta · Joined: 16 Aug 2023 Posts: 6

Back on topic.
The lens is indeed a rebranded Cosina Cosinon 50mm f1.7 offered with the Exakta Twin 42 TL camera, thus the M42 version (there was an Exakta bayonet version too). The Exaktar 50mm f1.8 is an almost identical rebranded Cosinon. More on the Exakta Twin TL cameras here: https://mikeeckman.com/2021/11/ihagee-exakta-twin-tl-1970/
The camera itself is a modified Cosina Hi Lite. Do not mistake it for Chinon Chinonflex TTL or Ricoh Singlex TLS which are almost identical between them and really different from the Cosina. A hint for all trying to guess the provenience of a particular lens: look at the camera it was sold with.
As mentioned above, what identifies this lens as a Cosinon are also the aperture ring cutout that was present on all early Cosinon M42 lenses (and never on Chinons), and the simple metallic tab of the A-M switch.
The formula is 6 elements in 4 groups (Biotar-like), similar to the Helios-44 in its ability to produce bokeh swirls.

The lens is really abundant as a Cosinon, Porst and Carenar branded lens. The most handsome variant is probably the Cosinon "zebra".
One more thing: these lenses have a protruding rear element (and its metal tube) at infinity, so one must be careful when using them with a (D)SLR.

MDPI · Joined: 15 Apr 2024 Posts: 6

alex_d · Joined: 19 Jan 2019 Posts: 339