My little collection of 35/3.5 presets

[Alex H]

These are the seven "names" I have collected over the last year. These lenses seem to me to be very similar to Kyoei/Kuribayashi/Petri 35/3.5 in optical and mechanical construction, except for having:

1) black and somewhat wider aperture ring instead unpainted narrower one;

2) blue coating in two specimens.

Hope it is of any use to the UVP community.

[nfoto]

A nice septet indeed. Are all for M42?

 

I have a similar lens labelled 'Westex' in Petri mount.

[Alex H]

Never heard of "Westex" before and I am not surprised. Who outside of Scandinavia ever heard of "Seastal-Ojasi"?

 

When we first started to discuss the Kyoei/Kuribayashi/Petri 35/3.5 preset on NG, and everyone started to look for those, driving up the prices, I found some of the ones that are in the picture. Few more came later on, but having 9 in total (I have two duplicates) is many more than I ever need. Most of the lenses I have are M42 mount, and few are in Exakta.

 

There is something really fishy about these particular lenses in the way they were branded. All the ones in the picture are names used by re-sellers in different countries: "Soligor", "Sonnagar", "W.Otra", "RolMax", "Seastal-Ojasi", "Mayfair Crystar", "Ina". Few of these names I have also seen on T-mount 35/3.5 presets of different shape and origin. Two other re-seller names to add to the list are "Votar" and "W.Taika Terragon". However, I have also seen identical lenses labelled with "Miranda", "Super Yashinon-R" and "Yashinon-R"...

[Andrea B.]

Alex, can you comment on the UV-capability of these lenses in general? Someone might like to contact you privately about taking a couple of them off your hands.

 

I'm beginning to think that I will devote a section in the Lens Sticky to 35/3.5 lenses as a general topic along with a list that skips the usual detail. I don't think I can possibly add all the above to the current Lens Sticky !!!!!!!

[Alex H]

I will do that, as soon as the sun comes out from behing the clouds, which may be as soon as ... next spring.

 

EDIT - I collected them over a long period of time and never had time to compare all of them at the same time. But I did use few of them.

[JCDowdy]

Lots of very familiar looking lenses with unfamiliar name branding (except Soligor of course). The history of these is murky. I have read that a lot of it goes back to Ponder & Best / Vivitar in the USA. They actually designed the lenses and contracted the manufacturing to lowest bidders, some sources say on an annually renewable basis. Apparently in post WWII German & Japanese economies this was something of a cottage industry. The folklore is that many of the losing bidders simply continued to make P&B/Vivitar designs to sell to any distributor in violation of design rights. I don't know how much of this is speculation but some of it seems credible enough coming from former Vivitar design engineers themselves. Also documented is that Vivitar had numerous lawsuits over this, with some former Vivitar contractors even importing counterfeit Vivitar branded lenses into the USA. It would take a real Sherlock Holmes to get to the bottom of the mystery.

[Alex H]

I do not know if Vivitar has anything to do here or not. The only 35/3.5 presets with Vivitar branding that I have seen are T-mount, but of course that does not mean anything. Few of the names in my collection are from European resellers: Seastal-Ojasi is thought to be Swedsih, but I have not seen any proof; Mayfair was a British lens importer. I have no idea about the others...

 

In cases like this, I think the name on the lens is the one that can confuse people the most. It's mechanical construction that I always check.

[igoriginal]

Glad to see that you also found a Kuri / Kyoei clone with an "Otra" on it, Alex.

 

Until now, I thought I was the only one in possession of such a copy. Thus, it has been an "orphan" for so long. (Looked everywhere, all over the internet for the past 2 years since I've found it, but absolutely no mention of it, whatsoever).

 

However, my copy simply states "Otra" by itself. No "W" in front it.

 

The "Votar" clone, I also found (3 years ago).

 

Here, I just snapped a photo of mine. Below are the "Otra" and "Votar" taken from my extensive Kuri / Kyoei clone 35mm F/3.5 collection (I have over 80 clones, now, and STILL building the collection to date).

 

Another seemingly "unknown" clone which I've discovered is branded under "Retro-Lumaxar" (at right). I have many other strange and "unknown" names, besides this one.

 

My copies of the "Otra" and "Votar" are EXACTLY identical to the Kyoei / Kuri M42 mount (permanent M42 / screw mount at base), and also even the same golden coatings.

 

The "Retro-Lumaxar", on the other hand, is a "T-mount" variant, and some hints of bluish colors in the coatings.

 

In real-world use, however, they essentially produce the same UV results - more or less (even if subtle differences in transmission curves are found, through spectrometer testing).

 

[igoriginal]

Speaking of EXACT Kuri / Kyoei 35mm F/3.5 clones (with permanent M42 / screw-mounts at the base, and golden coatings) ... another example of an oddity that I cannot seem to find any information about, anywhere, is the 'R. Bencor' (lens at right, next to one of my copies of another identical clone, the 'Taika Terragon').

 

This 'R. Bencor' was found at a flea-market that I attended regularly, and it was actually bundled in with a 35mm film camera set, under the "P & B" label (of 'Vivitar' fame). The lens was so stiffly attached to the camera, its rear element so clean and free of dust, and the black paint on its M42 threading looking so dark and fresh, that it made me consider that this lens might have truly been the original "kit" bundled with the camera sale, and has never been dismounted from the camera.

 

So, it does make my wonder if Vivitar itself (back to its "P & B" days) had even had its own sub-marketing divisions and partnerships.

 

In either case, as stated, the 'R. Bencor' re-badge is identical to the Kuri / Kyoei 35mm F/3.5 in just about every respect, down to the permanent M42 base and golden coatings (although, of course, we know that variations in the actual cosmetics and extrusions of ring designs exist).

 

[Alex H]

I was never interested in gathering data on the T-mount preset 35mm F/3.5 lenses, they did not attract my attention. But the Kyoei/Kuribayashi lenses are interesting to me not only due to their useful UV responce, but also by the way they are built.

 

First of all, their mounts are in fact interchngeable, but only between the lenses of the same focal length (and aperture). The picture below will show two repranded Kuri 35mm F/3.5, one with Exakta mount and one with M42. The mounts are secured by three tiny screws. They can be removed and changed. Similar mount system I have seen in 80mm and 105mm lenses from the same manufacturer. But they are not interchangeable between 35mm, 80mm and 105mm lenses. Only between the lenses of the same focal length. I think some German made lenses used the same approach even after the T-moun system was introduced in Japan. Unfortunately; I have only seen 35mm Kyoei/Kuribayashi rebranded lenses of this type (not T-mount versions) fitted with M42 and Exakta mounts, and my 80mm lens came with Miranda M44 mount.

 

 

The other peculiar thing with these lenses (35mm, 80mm, 105mm, 135mm and others) is that their entire optical block can be easily removed and separated from the focusing helicoid. It is very helpful when one gets the lens with completely frozen focusing, like I did. I tried to re-lubricate the focusing mechanism but failed miserably (and I have succesfully re-lubricated over a dozen lenses made by Zeiss, Minolta, Tamron, Meyer-Optik etc). Now, having some lenses with bad focusing but clean optics, and few with bad optics and fully functional focusing, I can "make" fully operational lens.

 

 

And the optical block can also be retrofitted with its own mount and fitted to the longer focusing helicoid. I have the 35mm lens head mounted on the 25-55mm focusing helicoid. The camera adapter had Baader-U2 mounted inside. This offers very compact package with excellent close-focusing capability (and infinity) for UV-only imaging.

 

 

[JCDowdy]

......

First of all, their mounts are in fact interchngeable, but only between the lenses of the same focal length (and aperture). The picture below will show two repranded Kuri 35mm F/3.5, one with Exakta mount and one with M42. The mounts are secured by three tiny screws. They can be removed and changed. Similar mount system I have seen in 80mm and 105mm lenses from the same manufacturer. But they are not interchangeable between 35mm, 80mm and 105mm lenses. ........

 

Interesting, all of the samples I have examined have fully removable T-mount adapters. I have separated some of these the T-mount adapters, removing the inner female T-thread indexing ring from the outer camera specific bayonet or screw mount and found that the ring is often incompatible with other T-mount adapter outer sections. On the lenses you describe, are the female T-thread rings cemented or preened onto the male lens T-threads?

[Alex H]

If I was not clear before, these lenses do not use T-mount system.

[igoriginal]

First of all, their mounts are in fact interchangeable, but only between the lenses of the same focal length (and aperture). The picture below will show two repranded Kuri 35mm F/3.5, one with Exakta mount and one with M42. The mounts are secured by three tiny screws. They can be removed and changed.

 

Yes. This I am aware of.

 

What I mean by "permanent mount" (as opposed to T-mount systems), is the minimal functional mounting unit. (Without modifications, removal of screws, surgical alterations, or any additional work that was not originally intended by the lens designer).

 

Thus, in terms of the "first generation" Kuri / Kyoei 35mm F/3.5 designs (before the introduction of the "universal" T-mount, which is also the minimal functional mounting unit of such a lens), the M42 / Praktica / Zenit thread-mount (or alternatively, Exakta bayonet mount) was the lens's minimal functional mounting unit. Sure, these could be additionally removed and swapped, but what was found underneath the removable mount after removing the screws (a groove-containing circular "U-plate", which the screws of the removable mounting unit were slid into and frictionally fastened against) was not its own functional unit (in terms of readily-mountable onto a camera body).

 

So, this is what I was trying to say by the words "permanent mount" (as opposed to a "universal" T-mount); The minimal functional mounting unit of the lens. I apologize for the lack of appropriate wording. :)

 

You're the optics expert, not me. But I keep learning, thanks.

 

I was never interested in gathering data on the T-mount preset 35mm F/3.5 lenses, they did not attract my attention. But the Kyoei/Kuribayashi lenses are interesting to me not only due to their useful UV response, but also by the way they are built.

 

Yes, the "permanent mount" designs definitely have some advantages, over the later-produced T-mount variants.

 

One of those advantages over the older design is that the rear element is not quite as vulnerable to progressive impact / abrasion damage like the later T-mount variant, which could easily be damaged by someone unwittingly placing an un-capped lens onto a hard surface, repeatedly, rear-side down.

 

(And this, indeed, seems to be quite a common issue with acquiring the T-mount variants. Many less-cared for lenses of this design often have some level of abrasion / superficial scratches across the rear element, if not at the very least some uneven coating loss / rub marks).

 

However, one thing that the T-mount design variant does have as an advantage over the older "permanent mount" designs ... is that the rear-element retaining ring which holds the elements fastened in place can be screwed off and removed by hand, and any damaged elements easily swapped with another lens of the same design, all in a matter of seconds. (No tools required, unlike the necessitation of having to use a lens wrench for accessing the "turning notches" on the older designs, just to open up the lens).

 

Another advantage that I feel the T-mount variant has over the older design, is more flexibility in mounting adaptability (especially with helicoids, bellows, etc., and cameras with different registers / flange distances) while properly retaining infinity focus and being able to obtain some good macro magnifications at the same time. All while going "tool-less" (no tool-based mods required, or even any removal of screws. Simply have an assortment of readily-available adapters for each camera body, and you're ready to go).

 

However, I concur with you that the earlier designs seem a pinch more durable. And, of course, with more simple coatings, the UV-A transmission curves of the older designs have been shown (according to some spectrometer readings taken by Dr. Klaus Schmitt) to have much somewhat higher transmission curves, especially toward the deeper ends of the UV-A range.

 

I guess, ultimately, it all depends on what one prefers, right?

 

But, after shooting with both types of mounting variants (the "permanent mounts" and the "universal T-mounts"), I have to say that overall, their UV usefulness is just about nearly (if not normally imperceptibly) identical in results, in real-world use.

 

Thank you for this dialogue, Alex. I immensely enjoy hearing from someone who has been collecting the same types of designs. And I appreciate you contributing some of those mounting ideas / suggestions, and associated photographs. That is very insightful, and useful.

[igoriginal]

By the way, Alex, I had to smile when you shared with me the occasional need to add on your own, custom-made "focusing module" to a lens that had its own focusing unit cease working correctly, jam up, or even strip (thus, necessitating its removal, and replaced with a make-shift or custom-made replacement). :)

 

I've had to improvise like this, with some lenses, too. And, of course, I've had to buy focusing helicoids of multiple lengths and ranges, until one would best suit my focusing range preference. For me, that preference is to retain infinity focus. But not only that, but to have my infinity focus occur exactly and precisely at the end of the focus throw of the modded unit, with absolutely no remaining slack (just as precise as the native focusing unit / block).

 

To accomplish this task and fine-tune the focus to this precision, however, I've had to use 'JB Weld' (a "cold-weld" type of epoxy-mixing adhesive that works extremely well for metals), and weld on readily available filter-extension rings or very thin macro rings (to add extra length to the end of the focusing unit, usually several millimeters at a time), until I could come as feasibly close to the lens's original focusing throw range on the infinity side, with no remaining play.

 

This way, I would eliminate any chance of unintentionally and accidentally "over-focusing" (going past infinity).

 

Of course, not everyone cares about such precision. And many UV-floral photographers usually don't even need to retain infinity focus at all.

 

However, since I do other type of work with the same lenses (besides UV-work), including landscape photography, then of course I have different needs. And then, there are even those who want to do landscape photography within the UV work area (like yourself).

[JCDowdy]

If I was not clear before, these lenses do not use T-mount system.

No, you were in fact precise in what you said, my question however was not.

 

What I am attempting to inquire is whether or not the inner half of the indexing junction you separated, which is analogous to the female T-thread ring of the T-mount system, is removable or is it integral to the lens barrel like the analogous male thread of the T-mount system?

[Alex H]

Thanks, Igor, for confirming my notes, which are in part based on disassembly notes that Steve Smeed published once for this lens.

 

Unfortunately, I got too fascinated with these lenses and gathered too many of them. After I figure out how many spares I actually need, the rest will have to go.

[Alex H]

No, you were in fact precise in what you said, my question however was not.

 

What I am attempting to inquire is whether or not the inner half of the indexing junction you separated, which is analogous to the female T-thread ring of the T-mount system, is removable or is it integral to the lens barrel like the analogous male thread of the T-mount system?

 

John, I still do not understand your question. There is no thread anywhere there. The lens mount is held by three screws located on the outer ribbed sides of it. There is a grove around the bottom part of the barrell of the lens, where these screws go. Moreover, on the bottom of this grove there are three unthreaded holes, where tips of the screws fit when completely recessed. They ensure the correct position of the adapter, so that the lens markings are facing the top when the camera is used.

 

The bottom part of the lens barrell is composed of several circular parts, two of which you can see on the pictures: the outer painted black and the inner unpainted that looks like brass. They are parts of the focusing mechanism (do not ask me how it works as I am not going to take apart these lenses any more), and have nothing to do with the lens mount itself.

[JCDowdy]

John, I still do not understand your question.

Perhaps not, but you provided the answer I seek nonetheless!

 

There is a grove around the bottom part of the barrell of the lens, where these screws go....

Answer = not removable, integral to the lens barrel.

 

I have not examined one like you describe, hence the naive question.

All of mine, including one acquired from you, are the removable T-mount type, hence my confusion.

 

Apologies for persistent ignorance, gratitude for curing same.

[igoriginal]

I have not examined one like you describe .....

 

All of mine ..... are the removable T-mount type.

 

I've got plenty of BOTH designs for you to test, JC, once we finally collaborate and I drive up there with my entire treasure chest of lenses. :)

[JCDowdy]

Should be an interesting comparison Iggy.

The project has been on the back burner for so long I hope it don't fall off the back of the stove!