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The Big Sankyo Kohki/Komura Thread
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PostPosted: Thu Dec 20, 2018 7:05 am    Post subject: Reply with quote
Oldhand wrote:

I tried a couple of the later zooms and was struck by their inferior build quality compared to the earlier lenses.
Optically they were also quite ordinary.
The best zoom that I have from Komura is their Super-Komura Uni Auto f4.5 75-150.
It really is excellent with very warm rendition


Thanks for this interesting info.
There is not much about Komuranon zooms, and also about Soligor C/D ones - which is another "family" of lenses I'm interested in - on the Web. In both cases the comments are lukewarm, if not cold, but I guess there should be some specific objectives that fare better than the others...

Trying to find facts about Sankyo Kohki (or Koki) Komura lenses, I realised that there is very little on the optical designs.
The catalog on cameraeccentric.com gives the number of elements of each lens, but there is no mention of the number of the groups they are organised into.
I found a couple of cut-outs, that's all.

Specifically, the short teles are all reported as having 5 elements, and some as having an Ernostar-derived design.
Though I couldn't find any optical diagram of all the lenses I own, but one (which is still in the mail).
The only lens I partially opened is the 2.5/105mm.
The two front glasses are positive, the second thicker than the first. I didn't pay attention, I can't say if there is only one element behind the diaphragm, or two. The same for the assembly in front of the diaphragm, can't say if there is one element, an air-spaced doublet, or a cemented doublet.
Any information about the lens design would be extremely interesting.


Here is what I found:



Komura 1:1.4 f=85mm cut-out




One question for those with better knowledge of the subject.
When people write that the fast Komura have "Ernostar design", what does it mean in practice?
The orginal design was 4E/4G, then it rapidly evolved to evolved to a more complex design where the second element becomes a cemented triplet... then it becomes the Sonnar! Smile
See these two Ernostars (first model and 1924 6-elements design):




This is the design shared by an early Ernostar 100mm f/2, and by the Leitz Elmarit 90mm f/2.8 and Minolta MC Tele Rokkor-QD f/3.5 135mm:



I'd say that THIS is the classic Ernostar design, with 4E/4G.
The five elements design of of some Komura teles (but the fastest 1.4/85mm, that has a seven elements design) are said to be Ernostar, but I always thought that the real Ernostar had 4 elements... so here I am at a loss.
Following the same line of thought the original Sonnar is an Ernostar too... but we still call it a Sonnar, not Bertele's modified Ernostar Smile
The following ones are Bertele's Ernostar evolutions:





Another issue I could not come up with is the existence of rebranded Komura-made optics.
I found conflicting opinions.
lens-club.ru (the russian version of the site) reports that a Kyoei Super Acall 135mm was manuafactured by Komura.
I have the same Super Acall, or one almost identical, but I own no early Komura lenses in Leica mount, so I have no way to know if there are similarities.
This is the lens on lens-club.ru (picture is their copyright):



And this is my Kyoei Super Acall 3.5/135mm (one of the very few LTM lenses I still have):




Now the question is, is there a Komura (LTM) that looks the same?


EDIT:
Found the answer by myself.
Here is an early Komura f/3.5 135mm in Leica thread mount, that looks more or less the same as the Super Acall:



I invite all the fellow forum users who are aware of some interesting info about Komura (and rebranded) production, to post here their findings.
I hope that my humble efforts will be appreciated, and (much more important) will arouse some curiosity about this brand and its history.
I will continue with a few more post with pictures of my other lenses, and I will also try to show some test photo.
I don't have many in the USB HD I have with me at the moment, and the few I have are just boring tests.
I will try to shoot a few pictures worth posting, trying my best to show center sharpness and bokeh.

Last edited by cyberjunkie on Sat Dec 22, 2018 7:53 pm; edited 1 time in total


PostPosted: Sat Dec 22, 2018 7:02 am    Post subject: Reply with quote
For further comparison, here is my Sankyo Koki Komura 3.5/135 - in LTM I think - haven't received it yet so can't say for sure
Note - Koki -spelling - no "h"
Tom


#1


PostPosted: Sat Dec 22, 2018 7:43 am    Post subject: Reply with quote
Oldhand wrote:

Note - Koki -spelling - no "h"


Yes, it seems that the early choice to transliterate the japanese in roman characters didn't involve the use of "H" Smile
So it was Koki instead of Kohki.

I found this problem countless times in my own experience, living in India, Nepal and Thailand.
The same government bureaucracy uses two (or even three or more!) different names to indicate the same place/structure.
The map has one, the sign at the intersection has another, and the placard at the front yet another one!
Transliterating an alphabet to a different one calls for conventions, but unfortunately there is no widely accepted convention.
If you want to learn thai language without learning its complicated alphabet you'd find out that YMCA uses one standard, and other respected schools use another one, quite different. No surprise that road signs are as confusing.

Cheers
Paolo


PostPosted: Sat Dec 22, 2018 9:12 am    Post subject: Reply with quote
Komura made very good enlarging lenses, at the same level of Schneider and Rodenstock non-apo's.
Some Komuranon's were ordered by Durst for their top-quality line of enlargers.

The line of enlarger lenses, of double gauss design like the competitors, were initially named Komuranon-S, and then Komuranon-E.
I am not aware of any difference, they look very similar, and possibly most designs stayed the same. The E line added a 135mm to the pre-existing focals.
In digital times, the longer ones can be turned into macro-hunting lens heads, on a bellows, and preferably with a flash. Their not-so-great max aperture and the manual diaphragm call for a slow, well thought use. A tripod would help.
The 50mm could possibly work well for higher reproduction ratios, used reversed.
I still have to experiment, and see if a ready made reversal ring (or a combination of them) is available for cheap on eBay.
Some very good enlarging lenses, like the Leitz Focotar, are not easy to reverse because of the lack of a front thread.

Here are the two I have, one Komuranon-S 5.6/150mm and one Komuranon-E 5.6/75mm:






And here some info:

Komuranon-E



Komuranon-S



PostPosted: Sat Dec 22, 2018 9:39 am    Post subject: Reply with quote
Yes, the Komuranon enlarging lenses are very good in my opinion.
Thank you for the information in your post.
I have the Komuranon-S 3.5/50 which I rate better than the EL Nikkor.
Must try these out on bellows and see what they do in macro shooting.
Tom


PostPosted: Sat Dec 22, 2018 9:20 pm    Post subject: Reply with quote
Here is a very common Komura lens - the 135mm f2.8 pre-set.
A lovely, low contrast lens that likes to have a lens hood for best results.
Images as shot except for mono treatment in NIK.
Tom


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PostPosted: Sun Dec 23, 2018 10:57 am    Post subject: Reply with quote
Like 1 Like 1 Like 1 very nice ones Tom!


PostPosted: Sun Dec 23, 2018 11:02 am    Post subject: Reply with quote
Oldhand wrote:
Yes, the Komuranon enlarging lenses are very good in my opinion.
Thank you for the information in your post.
I have the Komuranon-S 3.5/50 which I rate better than the EL Nikkor.
Must try these out on bellows and see what they do in macro shooting.
Tom


Yes, they indeed are very good lenses, I have a few Komuranon-S lenses myself (50mm, 75mm).
They can also be used for reflected UV photography:
http://photographyoftheinvisibleworld.blogspot.com/2012/12/quartz-fluorite-len-vs-enlarger-lens.html





PostPosted: Sun Dec 23, 2018 3:40 pm    Post subject: Reply with quote
I've got a couple of the 135mm f/3.5 lenses, here's one of them...

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PostPosted: Thu Dec 27, 2018 1:32 pm    Post subject: Sankyo Kohki W-Komura 1:3.5 f=28mm UNI AUTO Reply with quote
Here is the last Komura I got.
It's in UNI AUTO M42 mount, which means that the mount can be exchanged with others (Minolta, Nikon, Konica, etc), and that it has an auto diaphragm. The Man/Auto switch on the lens can also be conveniently used to stop down the iris with the push of a finger to the working aperture, after focusing wide open.
Here are a few pics:

Sankyo Kohki W-Komura 1:3.5 f=28mm UNI AUTO (M42)









And here is the cut-out of the optical layout. It seems to be Plasmat-derived:



PostPosted: Thu Dec 27, 2018 10:35 pm    Post subject: Reply with quote
Sankyo Kohki W-Komura 1:3.5 f=28mm UNI AUTO (M42)

That is an interesting lens and lens design.
I would be most interested in seeing some of your images taken with this lens - if you can manage it.
Thank you for sharing
Tom


PostPosted: Fri Dec 28, 2018 11:30 am    Post subject: Reply with quote
Oldhand wrote:
Sankyo Kohki W-Komura 1:3.5 f=28mm UNI AUTO (M42)

That is an interesting lens and lens design.
I would be most interested in seeing some of your images taken with this lens - if you can manage it.


Just shot the first test pictures Smile
I will post a couple of them, as soon as I find the time to shoot a few more and upload them to my computer.
First impression:
it seems sharp enough, and considering the age, it has a very good MFD (30cm). Some lenses of the same age can't focus so close!
The almost symmetrical design suggests good performance at close focus, and I believe it could work well reversed (for higher magnification), either on its own or fitted on top of a good 135mm telephoto.


PostPosted: Fri Dec 28, 2018 11:39 am    Post subject: Reply with quote
kds315* wrote:


Yes, they indeed are very good lenses, I have a few Komuranon-S lenses myself (50mm, 75mm).
They can also be used for reflected UV photography


Nice pics!
That would be a way to make good use of them... in case I decide to have my Pentax K-01 converted for use outside the visible spectrum.
Being a mirrorless, the conversion is cheaper than with other cameras.
I have other APS-C cameras for conventional use, and in all sincerity I am not using very much any of them, after I bought the K-1 full frame (which finally gave me back the same format 35mm vintage lenses were designed for).
So the conversion would be a good way to make the K-01 more useful.
You are the authority here, if I ever decide to do it, should I go for full spectrum or IR?
The first option would allow to shoot also UV, as far as I understand (I didn't study the matter very much Smile ) but I am afraid that decent cut filters would increase the expense too much...


Btw, EL Nikkor's are believed to be quite good for macro use (even beyond 1:1 magnification ratio, if reversed).
Your statement about Komura-S enlarging objectives makes me think that they should be a very interesting option for macro photography.
I always knew that they were top performers (at least before the release of the Apo's from Rodenstock and Schneider, and the Computar DL line).
Placing them ahead of the EL Nikkor's means that you give the Komura's a lot of credit. I feel encouraged to experiment and find a way to mount them reversed.


EDIT:
Instead of posting yet another message, I am attaching a little question to this one.
Anybody out there owns a Soligor with serial starting with "A"?
I found online that Soligor lenses with an A at the start of the serial are believed to be Komura-made.
I don't have any solid evidence of that, and I have never seen any Soligor with such serial... but I have no reason for not believing it is not true.
I am very curious to actually see one, though Smile


PostPosted: Sun Dec 30, 2018 11:38 am    Post subject: Reply with quote
Oldhand wrote:
Here is a very common Komura lens - the 135mm f2.8 pre-set.
A lovely, low contrast lens that likes to have a lens hood for best results.


Here is a picture of the same lens.
I already posted one of the f/3.5 version.
The two of them, and yours, share the same peculiar yellow engravings in the meters scale.
The lenses with this kind of livery always have UNI mounts, while most (all?) of those that don't have such visible touch of colour, are fitted with Komura's own interpretation of the T-mount.

Sankyo Kohki Komura 1:2.8 f=135mm in UNI M42 mount





Here are the two versions of the 200mm.
The faster one is the longest focal that has a 5-elements design. The f/4.5 version, and all the longer ones (300mm, 400mm, 500mm), all have a 4-elements design.
The 4.5/200mm is often seen in Leica mount, and is the longest lens that came coupled with the Leica rangefinder system.
Longer focals were designed for Komura's own version of the Visoflex.
Interestingly, in the Cameraeccentric.com catalog the 4.5/200mm is present only in Leica version. The version for SLR cameras was already out of production at that time.

Sankyo Kohki Komura 1:4.5 f=200mm in M42 mount




And here is the f/3.5 version. Pics from the seller. Now it's cleaned! Smile

Sankyo Kohki Komura 1:3.5 f=200mm in UNI M42 mount




Unfortunately I don't own the 400mm, and I don't have with me the 4.5/200mm and the 5/300mm, so I can't post any example of photos taken with those lenses. The 200mm was a bit wobbly, and needed a radical disassembly to get rid of the problem. The 300mm was not a great performer either, so both of them are in Italy now, and relegated to collector's items rather than usable picture-taking tools.
The 200mm could benefit from a good CLA, though. Maybe it's better than I thought...

I still have no idea about the lens design of the short/medium teles. All of them have a 5-elements layout, but I have no additional info.
Maybe they have the same (Ernostar-derived) design, maybe not.
Knowing the number of groups, not just elements, would help a lot.


PostPosted: Sun Dec 30, 2018 11:37 pm    Post subject: Reply with quote
cyberjunkie wrote:
. . .
Knowing the number of groups, not just elements, would help a lot.



Happy New Year ! Smile

©1963 brochure :


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Tim


PostPosted: Mon Dec 31, 2018 5:26 am    Post subject: Reply with quote
Thank you! Thank you! Thank you!


PostPosted: Mon Dec 31, 2018 5:47 am    Post subject: Reply with quote
Thank you Tim, that is a valuable resource.
Interesting that the 105mm f3.5 LTM isn't mentioned there, and is supposedly a five element design.
Others are quite intriguing
Tom


PostPosted: Mon Dec 31, 2018 6:52 pm    Post subject: Reply with quote
kds315* wrote:
Thank you! Thank you! Thank you!


Oldhand wrote:
Thank you Tim, that is a valuable resource.
Interesting that the 105mm f3.5 LTM isn't mentioned there, and is supposedly a five element design.
Others are quite intriguing
Tom



Welcome Turtle


PostPosted: Wed Jan 02, 2019 7:26 am    Post subject: Reply with quote
The 1963 catalog is a GREAT addiction to this thread! It answers a lot of questions and calls for a couple new ones.
The 28mm 1:3.5 in UNI AUTO mount is probably different from the almost symmetrical 6-elements design I had already posted. The lens with the same optical layout that is at the start of the 1963 catalog is a rangefinder lens, with no retrofocus design. I believe the SLR version to be different.
It would be great to find a similar catalog from the early seventies. It would make many things much clearer.
Another question I can't answer: are the fixed-mount 3.5/135mm all triplets, and the UNI versions all 5-elements?
The Cameraeccentric catalog reports the 3.5/135mm as 5-elements, just like the f/2.8 version, while the 1963 catalog, that very likely predates the Cameraeccentric one, reports that both the rangefinder and SLR versions of the 3.5/135mm were triplets.

EDIT:
found the info I overlooked, the 3.5/28mm Auto is in fact an 8-elements design.
So Komura sold at the same time two versions of the 3.5/28mm. One is UNI mount, and has 6 elements like the rangefinder one. The other has UNI AUTO mount, and has a modern 8-elements design.


Please surprise us again with more scans of old leaflets, or with links to Web pages with interesting info.

Wish you all a relaxed, fulfilling new year
Paolo

Last edited by cyberjunkie on Wed Jan 02, 2019 12:58 pm; edited 2 times in total


PostPosted: Wed Jan 02, 2019 7:37 am    Post subject: Reply with quote
cyberjunkie wrote:

Another question I can't answer: are the fixed-mount 3.5/135mm all triplets, and the UNI versions all 5-elements?
The Cameraeccentric catalog reports the 3.5/135mm as 5-elements, just like the f/2.8 version, while the 1963 catalog, that very likely predates the Cameraeccentric one, reports that both the rangefinder and SLR versions of the 3.5/135mm were triplets.

Please surprise us again with more scans of old leaflets, or with links to Web pages with interesting info.

Wish you all a relaxed, fulfilling new year
Paolo


I have both the 135/3.5 and the 105/3.5 RF lenses, and I believe them to be triplets.
They are both very good triplets mind you.
Tom


PostPosted: Thu Jan 03, 2019 1:48 pm    Post subject: Fast Komura's ad Reply with quote


PostPosted: Thu Jan 17, 2019 9:04 am    Post subject: Reply with quote
Another post will follow soon.
I am trying to investigate about two different matters.
One is the relationship between Komura and Acall. It seems clear that W Acall and Super Acall lenses in LTM mount were made by Komura. I have no idea if there is any relationship with Kyoei Acall ones. Trying to find photos that could prove (or disprove) it.
The other thing is the possible affinity between the UNI mount and the 47mm interchangeable screwmount used by Tokina. Both have the same diameter, but I have no idea if the register is the same. I have no lenses with Tokina M47 mount... so I'm asking for your help Smile


EDIT:
The isssue of the provenance of Kyoei/Acall lenses is a very complex one.
While I have seen many lenses marked either Kyoei Acall, W Acall or Super Acall that were clearly Komura-made, I have a Soligor with serial starting with KA (which I interpreted as Kyoei Acall) that looks very much Kuribayashi/Petri. The same lens was also sold marked Kyoei Acall (see marcocavina.com site).
Though there are Keyoei Acall lenses that look neither Komura nor Kuribayashi.
See this Kyoei Acall f3.5 135mm I just found on eBay.
It screams Hitoh (Higon). Look at the typical reference mark (round, in red, surrounded on three sides by a white square):



I have seen the same reference mark only on Itoh lenses, marked as Higon or under other brands... the last being a Tele Astra 3.5/135mm in Nikon rangefinder mount.

Last edited by cyberjunkie on Fri Jan 18, 2019 10:56 am; edited 1 time in total


PostPosted: Fri Jan 18, 2019 9:22 am    Post subject: Reply with quote
Like 1 small Thank you!


PostPosted: Sun Jan 20, 2019 8:54 am    Post subject: Reply with quote
Well i've got the 35 2.5 and 100 1.8 ,they come with a ring mount that can be exchanged . The focus on both and mechanics are soooo smooth.....i should try 'em up one of these days


PostPosted: Sun Jan 20, 2019 11:54 am    Post subject: Reply with quote
> Another issue I could not come up with is the existence of rebranded Komura-made optics.
(Cut from a post above)

I picked up a "Bitco Super Vemar" 135mm F3.5 in Leica mount, 46mm filter ring. It is identical to the 135/3.5 Super-Acall, so add another Komura Rebrand to the list. "Bitco"... this must be their brand designed for Digital Cameras.

This lens needed a lot of work, including relubing the helical. I had to mount the optical barrel into a spare Komura focus mount. The two halves of the helical would not go back together: until I widened the grooves. Advice: do not separate the helical to relube, the metal is soft and easily damaged. I did manage to re-assemble the original focus mount that came with the lens- but the one I had is smoother.

I also picked up the Komura 105/3.5 in Leica Mount. The focus is way off on this lens, the optical barrel stubbornly refuses to come out. Focus is smooth. I'm going to use a shim between an M-Mount adapter and lens to correct the focus. This should work as RF agreement and actual focus are both off, both close-focus.

Picked up a long time ago- Leica mount Komura 200/4.5. Finally picked up a 35-200 zoom-finder for it.
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