Kowa Six Lens Designs

Long-time lurker, first-time poster. I was hoping someone could confirm or correct my guesses about the designs of these Kowa lenses. I'm not sure how the order of the images will post, but from top to bottom my guesses are: Planar, Biogon, Ernostar, and Tele Tessar. Thanks in advance!

 

 

Can confirm nothing , except to say the 3 I have are great :). Peter

OP, appending the lenses' names would have been helpful.

 

Guesses? Looks more like a cut and paste job from Kowa Super 66 Technical Bulletin instruction manual, user manual, PDF manual, free manuals

Thanks for that excellent link, dan_fromm: hadn't seen that the last time I looked up Kowa in his archives.

 

Having owned a small Kowa Six MM system awhile back, from memory, the top lens is the standard 80mm, third one down is the 150mm, both of which I had (but in silver). Second one down is probably the rare 40mm, bottom one 250mm.

 

taylorbright, your optical guesses seem to fit except on the 40mm, which is almost certainly not a Biogon: if we're gonna go with a Zeiss-inspired naming formula, Distagon would be more likely. Biogons have substantial symmetry, Distagons are more retrofocus. An SLR like Kowa could not accommodate Biogon: this is why Hasselblad needed a dedicated non-SLR body as Biogon host, while their SLR 40mm was a Distagon. Wide angles for all other medium format SLRs would be similarly retrofocus. Even my Mamiya TLR 55mm Sekor (and the RolleiWide TLR) are retrofocus

Excellent! Yeah, I went with the Zeiss naming because they seemed to be Zeiss clones and made it easier to keep track. I hadn't even thought about the retrofocus on the Biogon. And, now, it makes more sense that it would be a Distagon because that's the Kowa 40mm f/4 and its Zeiss equivalent is a Distagon. Thanks again! P.S. You are exactly right on the lenses I posted! I have all of them except the 250mm. Throw in the 55mm and that's my whole collection.

Most medium format lenses across all film format systems were based on designs that date back to the stone age (of course modernized and updated). So referring to any particular lens system as a "Zeiss clone" is a bit unfair: Zeiss did indeed invent many wheels (and bought out many others), but the "cloning" done by other brands was perfectly legitimate. There's only so many ways to design a doorknob, esp back when optics were calculated by hand or crude computer programming (your phone is 1000x more powerful than whatever Zeiss used to calculate the 40mm Hasselblad/Rollei Distagon in 1965).

 

Kowa had an unfortunately brief foray into medium format: their 6x6 system was only offered for six or seven years. But Kowa did not need to "clone" anyone for their lens line: before ever getting into cameras, they were already a high end industrial optics company. During the short lifetime of their "budget" 6x6 SLR, they offered innovative options that would be unequaled by other medium format systems for another decade or more (19mm fisheye, 35mm rectilinear super wide angle).

 

Two aspects I found uniquely advantageous with Kowa were its incredible damping, and bright, contrasty, easily focused viewscreen (a rarity in MF before the 1990s). Unlike a Hasselblad, which jumps in your hand like a frightened cat when you fire the shutter, the Kowa is utterly smooth: you can't even feel the mirror slap. The only other MF slr that matches its damping is the Mamiya RB67. The standard focus screen is amazing: just snaps crisply in and out of focus with no uncertainty. That "snap" was hard to come by in MF cameras until screen tech ramped up in the '90s, and even then you often had to pay thru the nose to get it. I've used almost all the MF SLR and TLR systems at one time or another, the only ones with standard screens that could equal the Kowa "snap" were the final Mamiya TLRs (C220f & C330s) and the later-revision Rolleiflex SL66 SLR.

 

Poor marketing, body design miscalculations, and low brand recognition doomed the system prematurely. Some elements of the body design were exceptionally well executed (damping, viewing), some were good in theory but poorly executed (less convoluted film path), some were just plain bad (film advance gearing).The TLR-inspired L-shaped film path was far less twisty than competitors Hasselblad or Bronica, but made for an awkward ungainly body too tall for the nose-heavy SLR lenses. It also prevented interchangeable film backs, until the final model (too little, too late, and more clumsy). Mechanical problems with the advance became an issue (as it did in many other Japanese MF SLRs: this was a weirdly common defect).

 

These drawbacks might have been overcome, but the combination of no brand prestige, no backs, and iffy pricing undermined Kowa's chances. During its heyday it was trapped between Hasselblad at the high end and Bronica at the low end. The Seiko leaf shutter lenses gave Kowa a leg up on Bronica, but the lack of backs (until the end) crippled its potential as "poor man's Hasselblad". Meanwhile, Bronica had the cheapest lenses in town (yet with the desirable Nikkor name), interchangeable backs, brand recognition, and innovative bodies that got loads of press (EC/TL).

 

Kowa did maintain a small but passionate following, esp among wedding pros: the system was heavily promoted in the used camera listings of Popular Photography, Modern Photography, etc for many years after the system was discontinued 1975 (to a degree you'd assume it was hugely successful). Arguably, more photographers became aware of it after it ceased mfr than when it was current: interest seemed to peak around 1977-82. Today, its largely forgotten: the Bronica ETR/SQ long ago usurped Kowa's destinay as the true "poor man's Hasselblad".

Edited October 4, 2019 by orsetto

The first lens, an 85mm shares the same 5 element formula with the 110 macro.

This is the same formula Schneider used in the Xenotar that was mounted in the early Rolleiflexes.

They subsequently added another element for the more modern Rolleis.

This is the same formula Schneider used in the Xenotar that was mounted in the early Rolleiflexes.

Agreed. A Xenotar copy.

Most Planars are 6 element designs, and mirror symmetrical about the aperture, or nearly so. The Xenotar's 5 elements attempt to introduce some asymmetry, which helps with better controlling some aberrations.

 

Kowa's retrofocus wideangle is also very similar to a Schneider design; their 21mm Super-Angulon for the 35mm format.

 

The third, short tele, design is nothing like the Ernostar IIRC. The Ernostar is quite a unique and highly telecentric design, whereas this Kowa lens is much simpler and looks as if it was lifted from an Asahi Pentax Takumar design for a 105/120mm portrait lens; again for the 35mm format.

 

The telephoto lens bears the closest resemblance to the Leitz Telyt R.

 

So I suspect that Kowa's designers simply enlarged existing designs for the miniature format. Possibly avoiding some patent wrangles by doing so.

 

The above information is taken from comparison with diagrams published in Arthur Cox's 'Photographic Optics'. A very useful work for anyone interested in photographic lens design.

 

As a former Kowa 6 user, I have to say that the shutters in the lenses, along with the camera bodies, were the weak (very) points of the system. The interior of the camera was poorly built using thin materials. Hence the erratic frame spacing, due to a spacing disc bending if the camera is wound on slightly enthusiastically. It can be fairly easily repaired, but the design is inherently not robust.

 

Likewise with the shutters, which aren't made to a high standard.

Edited October 8, 2019 by rodeo_joe|1

they offered innovative options that would be unequaled by other medium format systems for another decade or more (19mm fisheye, 35mm rectilinear super wide angle).

Or so it was rumoured!

Those lenses were certainly advertised, but I've yet to verify that they actually made it off the pages of magazine adverts and into real existence.

 

I heard third hand Chinese-whispered tales of some guy in a far off place who owned a 35mm wideangle for the Kowa 6. However, no review of that lens, nor of the fisheye, ever seemed to reach the pages of the photo mags of the time.

 

In fact Mamiya weren't that far behind in making a rectilinear 35mm wideangle for their 645 system. A lens that you could actually buy and use!

If you try a google search for "Ross Yerkes service super wide" you'll see a youtube video of him working on a 19mm.

I remember seeing a 35mm on ebay but I didn't pursue it as I already had the 40mm.

They exist.

Did a search for the Kowa Six 35mm and this was posted by a Japanese camera shop last year (he remarked how incredibly rare it was.)

 

Only f/4.5? That must have been dim to focus, even with the Kowa's quite bright screen. But at least it looks like a wideangle, unlike their weirdly shaped 55mm lens.

 

Too bad about the crappy build quality. I actually liked the sit-up-and-beg ergonomics of the Kowa. Even if you couldn't open the back with a prism fitted!

On the Kowa Six flickr page there's a photo of one fellows collection that includes the 19mm fisheye lens. Missed my chance at

one from France (about 5 or 6 months ago ) , it ended up going for over $1000 ! Way outta my range. Absolute heresy Joe , how could one

call the 55 mm lens weirdly shaped :D ? (there's enough glass in that lens to make a telescope) Kowa lover forever , Peter

ps: I've 2 kowa Super 66's and 4 backs and they may have some quirks , but they all space frames evenly .Maybe I'm lucky ?

The Kowa 55mm wide angle lens barrel only seems weird to those who've never owned the once-ubiquitous Hasselblad Zeiss 50mm C Distagon. Interestingly, both companies had even more dramatically flared 40mm barrels, and both later revised the 55mm/50mm optics and barrels to be more traditional looking (the Kowa 55mm black revision of 1973 was first, Hasselblad lagged until their entire lens lineup got uniform barrel revamps with the 1982 CF update).

 

Kowa

 

Hasselblad

Edited October 9, 2019 by orsetto

In fact Mamiya weren't that far behind in making a rectilinear 35mm wideangle for their 645 system. A lens that you could actually buy and use!

 

I was thinking more in terms of leaf-shuttered lenses: Mamiya did indeed offer a 35mm rectilinear for the early M645 (and it was affordable!), but I don't think a leaf shutter 35mm turned up until the Hasselblad / Fujiblad H system in 2002. Bronica only offered 30mm/35mm leaf shutter lenses in fisheye format for the ETR/SQ, while Hassy/Zeiss had a 30mm fisheye. I don't think any other medium format vendor has ever matched the 19mm Kowa fisheye, with or without a leaf shutter: that remains a benchmark (albeit it almost doesn't count, given so few were ever actually produced).

Edited October 9, 2019 by orsetto

ps: I've 2 kowa Super 66's and 4 backs and they may have some quirks , but they all space frames evenly .Maybe I'm lucky ?

The advance mechanism was improved on the Super 66 from the 6 and MM - i.e. they stopped using a bit of old tin-can lid for the spacing wheel.

 

However, the Super 66 came a bit too late to quell the reputation for poor reliability that the Kowa 6 had gained for itself. The Super 66 is definitely the body to have... if you can find working lenses to fit.

 

The lack of availability of a fisheye lens is a distinct bonus in any system in my opinion. Never seen the appeal of the things apart from novelty value that quickly wears thin. And if you really must have a circular image with feet included (your own or your tripod's) then there are perfectly adequate screw-on converters for the job.

 

There were two releases of 55mm wideangle for the Kowa 6 BTW. The first version had a peculiar bullet shape that made it look more like a short tele. Confusing when you reached for it in the gadget bag without closely checking.

That early version of 55mm lens must be quite rare. There are pictures of it here.

 

It took a bit of searching to find pix of it online, and as you can see, it looks nothing like a Distagon.

I've had both versions of the 55 and as far as I remember the flared one is the oldest.

I have the impression that the 55mm started out with the flared objective end (86mm?), then went to the cylindrical chrome, then to the cylindrical black which allowed users to standardize on 67mm filters.

As far as rarity, ebay in Canada shows two black 67's, one chrome 67, and one chrome with the flare. They're one of the more common lenses in the Kowa line-up.

Maybe my memory is playing tricks, but I seem to remember early reviews of the Kowa system remarking on the narrow nose of, what was then, the only wideangle on offer for the camera.

 

Pretty sure it initially launched with just the 85mm standard, the 150mm portrait tele, and the bullet-nosed 55mm. I definitely remember being confused that the 150mm lens was more flared than the 55mm, especially after using a Zeiss Jena 50mm Flektogon on a Pentacon 6.

^^^^ #16 from Rodeo-Joes pictures ,that's certainly nothing like the 55 mm lens I have ( the early(ish)) silver one.

No mistaking it for a longer reach lens . They've certainly tested my camera repair patience ( first one , the super 66 )

the lens was inoperative , the back wouldn't advance past the first frame and the body had so many problems I had to

weld carbide saw teeth into the winding mechanism , just a quick 123 hrs .The back up super 66 only required

about 50 hrs , practice makes perfect ( perfect fools for spending so much time , but hey , it crappy in Vancouver in

the winter time .) Peter

I have the impression that the 55mm started out with the flared objective end (86mm?), then went to the cylindrical chrome, then to the cylindrical black which allowed users to standardize on 67mm filters.

 

Correct: rode_joe is remembering these versions slightly out of sequence. The exact timing of when they were released is unclear, it may have been been unusually quick (which could lead to owning bodies much newer than a particular 55mm lens, and vice versa). The flared nose silver version came first, and was widely criticized for requiring a huge 86mm filter. This led to the narrow nose silver update, which aligned its 67mm filter size to match the 85mm and 150mm lenses of a standard three-lens kit. The black narrow-nose just updated the finish to match the black Super 66 body color.

 

Back when numerous photographers still actually owned functional Kowa gear and used it, there was frequent debate over which 55mm version was optically better. Both are f/3.5, so many assumed the larger glass of the early version made it easier to correct aberrations (while the significantly smaller glass in the later version could have been more difficult to correct). I never owned the large flared Kowa, but thought my narrow-nose silver 55mm was OK, about on par with my early 50mm silver Distagon for Hassy (with similar diameter glass constraints). Neither was spectacular on 6x6: the much later floating-element Distagon wipes the floor with both. Realistically, I imagine the wide-nose Kowa would have similar performance to the wide-diameter (82mm filter) 50mm f/3.5 Nikkor I had for my Bronica S2A: a flare magnet if there ever was one.