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jnantz
27-Oct-2003, 18:39
hi there

i was wondering if someone can give me info on a zeiss protar triple convertible lens. i am was toying with the idea of buying one and using it as my primary lens on a 8x10. but i don't really know if it is worth the money. i know that some legends used them &c &c, but that isn't really what matters to me, it is contrast / flatness and image quality ... i'm not one for using many of the intermediate fstops, i usually shoot either wide open or down to about f22. i have read some of the archived threads about the b&l protars ( the same lens but for less money) but no much about the zeiss protars.

is it really worth the $$ it demands ( small fortune ) ... or will i be happy enough with something like a wollensak velostigmat which costs maybe 1/3 the price?

i'll primarily be shooting architectural subjects, remnents & broken down buildings in-situ, portraits, streetscapes landscape-y sort of things.

THANKS in advance :)

-john

Ernest Purdum
27-Oct-2003, 19:25
The Bausch & Lomb Protars are the same lens as trhe Zeiss, so whatevcer you read about the one would apply equally to the other.



There are many lenses that represent more value for the money; unless you really want to use the triple convertible feature (which would cause losses in the qualities you mention). The price of the Protars is also driven up somewhat by collectors.



For contras, try to find a coated lens. If a Wollensak, it will probably be called "Raptar" instead of Velostigmat and have a "W" inside a "C" on the front markings.

Kevin Crisp
27-Oct-2003, 19:39
I don't think anyone can reliably say that the Zeiss ones outperform the B&L ones across the board, certainly not to such an extent that the difference would be greater than the inevitable sample to sample difference within a product line. Is it worth it? Depends on the price. If you would be happy with just a 300 + or - mm lens, like a G Claron, then no, it is probably not worth it. Protar VIIa's that cover 8X10 are fairly rare in good shape, and cell combinations which yield a combined "normal" focal length for 8X10 seem to be exceptionally rare. The ones I have used and still use are exceptionally sharp when used combined and decent enough when used singly behind the shutter to make enlargments up to 16X20 off 5X7 film or 4X5 film. (The size being limited by my darkroom space, not by the lens quality.) I think a single protar used behind the shutter is way better than any convertible Symmar I've used, converted.) The single elements have some focus shift, so you have to adjust focus after stopping down. There are only 4 air/glass surfaces in a VIIa, since each component is four pieces of glass glued together -- the loss of contrast is noticeable under some circumstances but not anything more than a 1/2 grade or so versus a modern lens. I don't miss the contrast of a modern lens, but many would probably write these off based on that alone. While the idea of "3 lenses in one" is appealing, note that the 3 lengths are generally not what you would choose and can leave gaps big enough that you might want something else along too. Like 240/355/425, or 250/425/490, etc. MANY of these have some balsam separation; this is not big deal if just a slight ring around the mounting but many are much worse. You will be charged at least $300 per element to fix this, since the labor in separating and then recementing 4 pieces of glass is considerable. Many are in older shutters or even second generation shutters (Acme 4's, for example) that need a CLA. If you are dealing with issues like recementing and fixing shutters, the amount you will put into the project will be impossible to get back, at least in today's market. If you love them and have the money, you do it. But a good "investment" in the strict sense, it is not. If you are using one without an original triple engraved scale of f stops, and you have one just in millimeters, you have to carry a table you've worked out like the one shown on Wisner's web site for his convertible symmars. This slows you down, just as changing elements around slows you down too. For the people that use them, I don't think there is any question they think the protars are "worth it," but whether this is true as to you personally you will have to decide. As to Wollensak lenses, they can be quite a bargain and many are underappreciated. (I have a 15" tele Raptar that is awesome by any standard.) With a coated Wollensak you could get what you are looking for and probably buy several lengths that are what you need and not be stuck with the combinations of the protar. People sell used Zeiss and B&L sales books which is a good place to start to see the dizzying array of what is available in these classics.

CP Goerz
27-Oct-2003, 20:17
A Wollensak series 1a triple is/was one of the best triples made. The 13 1/2"-20"-25" combination should suit you just fine. They sell for around 250-350 in a shutter depending on condition.

Kevin Crisp
27-Oct-2003, 21:09
John: Also, I don't think you'd be particularly happy with any protar wide open, though I don't know why you shoot that way. They're just dandy f:22 and smaller.

Bill_1856
28-Oct-2003, 07:13
My limited experience with Protars showed a considerable focus shift on stopping down, and wide open they're not the world's sharpest lenses. I think they're more suitable for landscape than for architecture.

N Dhananjay
28-Oct-2003, 08:26
The Wollensak is a very well designed lens - the Protars are very good also but their cult status (esp. the Zeiss issue) makes many of the other convertibles much more attractive. The Protars are very good, but if it is contrast you are after, you will probably end up looking elsewhere. The image quality of the full Protar (unconverted) is similar to that of a Dagor - a somewhat smooth transition between tones and some added shadow detail, excellent resolution but it's not going to have the contrast of certain other kinds of designs or of modern multicoated glass. When used converted (i.e., using a single cell alone behind the stop), the performance is going to be worse than using the full lens. It's not bad (and actually, it's surprisingly good) but don't expect miracles - by removing one of the elements, you lose some of the corrections that rely on symmetry for correction. Performance can be improved by using a sharp cutting filter to restrict the spectrum (and reduce lateral color) and by stopping down (to reduce the other aberrations). The Protar single cells are actually particularly good because each single cell is fully corrected for coma - you can use Dagors as convertibles also but they really do need to be used at small stops. And single cells of Dagors don't make bad pictures either (see Lake and Frozen Cliffs, Ansel Adams). I've been perfectly satisfied with contact prints made from convertibles and I have also made 3X or so enlargements and been perfectly happy with them. If you are going to use them on an 8x10 and you intend to make contact prints, you are likley to be quite happy with a convertible design. The Wollensaks are very good. The B&L Protars are perfectly good (I haven't seen any startling difference between the B&L and Zeiss issue Protars). The Ross Protars are also well made. The convertible Symmars are good and come in modern shutters (but have only two focal lengths). The Turner Reich's are good but quality control is a bit iffy - centering the five elements in each cell is quite hard. Rarer convertibles - the Cooke is supposed to be very good, but it is rare and since it was Ansel Adam's choice, is astronomically priced. Goerz convertibles are rare as hen's teeth - you'll probably need to put your first born on notice about his impending sale to fund that lens acquisition. There are other casket sets out there as well.

As far as focus shift etc goes, it sort of depends. Focus shift is caused by zonal spherical aberrations - rays from the periphery of the lens are focussed at a different point than rays closer to the center. This means you have a range of focus. As you stop down, you cut out the rays from the edge of the glass and you can end up changing your mind about position of best focus. In that sense, focus shift is actually a bit of an optical illusion - the position of best focus does not change - it's just one's judgment about the same that does. Typically, if you focus based on contrast rather than resolution, you are likley to experience focus shift.

The important thing to keep in mind is that convertibles were designed as a compromise. The task of providing three focal lengths within one lens-shutter combination helped to keep weight and prices down but it did mean additional contraints on the lens designer. In general, optimising over a rnage will always involve some compromises compared to optimising for a specific point.

One last note - I strongly suspect that whether you will be happy with a convertible depends very much on your 'seeing' and what you want your prints to look like. A good place to start might be to look at Weston's pictures from his Guggenheim days - most of them are made with a Turner Reich or with a Protar element. Ansel Adam's pictures are also well worth scrutiny. He worked with all kinds of glass through his career - from convertibles and Daogors to Super Angulons - and he was more vocal about the technical end of things in his writings, so you know the details about what lens he used and how etc. If you end up liking his earlier work (and earlier printings), you are likely to be happy with convertibles or older design lenses. If you prefer his more contrasty, later printings and pictures, you are more likley to prefer modern multi-coated glass. It is hard to get a really good sense of image structure from a book reproduction, but it is a start.

Cheers, DJ

Michael Jones
28-Oct-2003, 12:29
I've used B&L Protars, convertible and single element, for years and found them to be admirable performers. However, nearrly all my work is contact printed. What some consider with modern glass as necessary sharpness for enlarging may not be as anticipated or expected in any older lens. Also, you must remember to use the single element behind the shutter and with a strong yellow (#15) filter to compensate for some of the shift. They should be stopped down to at least f22. One of my favorites is a 240/480; not only is it a moderate wide for 8x10, it is a wide for 11x14, and normal for 8x20 in its single element use at 480. There is a fine 590mm Protar single element that will cover anything you can get film for and its' perfectly sharp (for contact printing) and very compact.

Many Protars are available in fine shape; frankly, if you can find one already mounted in a Copal shutter, it tends to indicate that the owner felt strongly enough about the condition of the lens and its image quality to invest another $600+ in a convenience feature. Do not discount a lens mounted in a Compound shutter; if someone has not “fixed” it in a prior life, it can work well if rebuilt by a reputable repairman. Compounds were used into the 1970s and only taking some training to know how to use them.

Finally, as DJ said, look at the work of other artists who have used Protars. If the images have the quality you “like” and want to attain, give them a try.

Kevin Crisp
28-Oct-2003, 17:13
Just to add an observation...I do use the protars single and double, I do enlarge them, I do not use a yellow filter, and the prints look sharp enough that you can stick your nose right up to them and still think they look sharp. Maybe my standards are incredibly low. But I don't think so and I use modern glass too so I do have something else to compare them to. I'm adding this because I don't want somebody to give up exploring this idea because they think they have to use a K2 and only contact print; in my experience this hasn't been the case.

Chad Jarvis
29-Oct-2003, 11:48
Tsk tsk, DJ...you forgot to mention the venerable Goerz Pantar. Though rarer than hen's teeth, especially at the focal lengths required to cover 8x10, they are quite flexible. Most of what I've done has been with a 419/356mm combination (222mm combined) with sweet results. Granted the shots are not as high in contrast as an Artar, but adding a little time to development has been my remedy for that. As for sharpness, I have been absolutely amazed at how sharp the individual 419mm and 356mm cells are.

jnantz
29-Oct-2003, 12:32
thank you all for your help! i endeed up getting a wollensak triple and saved quite a bit of money :)

i had a feeling the zeiss was so expensive because of its "cult" stature, and since i don't see many of the b&l protars .. i thought i would just ask the folks that know more than i do :)

THANKS again

-john

ps. its just great having this forum back !

N Dhananjay
29-Oct-2003, 13:21
Hi Chad, That was merely my way of venting the jealousy I feel towards you...;-)

Chad Jarvis
29-Oct-2003, 15:12
DJ...just make me an offer!