Versions of Zeiss Luminar lenses
or: How old is that Luminar lens advertised on Ebay?
In a few other pages of this site (1, 2, 3, 4) I tested a number of Zeiss Luminar lenses, and of other lenses that can be used in photomacrography. The Zeiss Luminar lenses always turned out to be the best performers for this application, together with the Zeiss S-Planar 74 mm, among the lenses I tested. Zeiss Luminars seem to be actively sought by photographers as well as collectors. They come up quite often on auction sites like Ebay and, unless grossly overpriced or seriously damaged, never fail to sell. Most of the time, about half a dozen such lenses are simultaneously available on Ebay. Depending on the condition and model, actual selling prices usually range in the 250-450 € for a specimen in prime condition. You can find sellers asking twice these prices, but this does not mean that they actually sell their items. In fact, some of these overpriced items have been advertised for years and have become "a part of the landscape" one becomes selectively blind to.
Not many sellers nor potential buyers are aware of the fact that these lenses have been produced during a time span of at least 40 years, and in successive versions that differ in both mechanical and optical respects. Although I certainly do not claim to be an expert on the history of these lenses, I have collected a number of observations that may be useful to users, collectors and buyers. If you intend to acquire one or more of these lenses for the purpose of using them to take pictures, perhaps you are interested principally in the later versions. Although my tests have failed to show any significant differences in pictures taken under realistic conditions with lenses of different versions, the later versions might have a slightly better resolution and contrast. In any case, if in prime condition, later versions certainly cannot be worse than earlier ones, and are less likely to have hardened grease or oily diaphragms. On the other hand, you might pay a lower price for a Version 1 or 2 Zeiss Luminar (see below) and, in most cases, still get pretty much the same lens in terms of optical performance. If you are a collector, the "right" price may be determined by factors I am unaware of, because my own interest is primarily as a photographer and user of these lenses. This page may help you not to pay too much for an older Luminar versions if this is what you seek, or to get a modern version if you are actually looking for one.
Information on the exact production years of different versions of Luminar lenses is especially scarce. Unless Zeiss will make this information available, this situation is unlikely to change. None of the Luminar manuals I have seen is dated, and very little Zeiss literature on these lenses is available in any case (especially of the later versions). The following table is copied from a 1974 Zeiss price list, and shows all Luminar models except the Zoom (see below). At this time, Version 2 Luminars (described below) probably were being produced.
Luminar Focal Length: 16 mm
Catalog Number: 46 25 11, 46 55 61, 46 55 42
Aperture d/f: 16 mm/1:2.5
Maximum Aperture, d/f : f: 0.2
Diameter of Maximum Specimen, fld. Coverage mm: 5-6
In this page, I use only illustrations of lenses I own. In the past couple of years, I have seen other specimens, as well as at least two hundred pictures of Luminar lenses from Ebay auctions and web sites. I will not reproduce any of them here, because they may be protected by copyright, and/or sellers may not wish them to be re-published. Nonetheless, I am discussing in the text several details that should easily be recognizable even without pictures. The Macro Lens collection database site by Dr. Klaus D. Schmitt contains numerous pictures of these and other photomacrographic lenses (albeit not of all the Luminar versions).
Often, photomacrographic lenses with small barrels, manual irises and typically an RMS mounting thread are called Luminar-type lenses. However, Zeiss Luminar lenses are neither the only, nor the first lenses of this type. A 1941 Carl Zeiss Jena catalog, for instance, lists the following lenses for macro photography and photomacrography, all for use with the Utraphot 1 system:
Tessar 16.5 cm f/6.3 (perhaps made by Leitz?)
Mikrotar 9 cm f/6.3.
Mikrotar 6 cm f/4.5.
Mikrotar 4.5 cm f/4.5.
Mikrotar 3 cm f/4.5.
Mikrotar 1.5 cm f/2.3.
Mikrotar 1 cm f/1.6.
This page deals only with Luminar lenses produced by Carl Zeiss West Germany (or Carl Zeiss Germany as the company used to call itself, even though at the time there were a West Germany and an East Germany). Eventually, Carl Zeiss gave up the Carl part and started using just theZeiss name and the West Germany label on Luminars. By the time Germany was re-united, Zeiss had already stopped making Luminars.
company revived in Soviet-occupied East Germany was usually called Carl Zeiss
Jena, although often, and purposefully, marking its products in a way that might
confuse them with those of its western counterpart. They never made Luminars,
and their equivalent lenses were the Mikrotar series (not to be confused with
Leica's Makrotar and Spiratone's Macrotar). In the Soviet Union, Lomo received most of the equipment and technicians plundered from the German factories by the Soviet army at the end of World War 2, and produced a series of Mikroplanar lenses. These are not substantially similar to the Luminars. In West Germany, Leitz produced a few series of Photar photomacrographic lenses as well, which were regarded as direct competitors to the Luminars. Nikon, Olympus, Minolta and Canon, together with lesser-known Japanese, European and US brands, also produced lenses similar in general design to the Luminars. Canon might still be producing a couple of models. Zeiss made other types of lenses for macro and photomacrography, including a few S Planar designs (like the S-Planar 74 mm).
In the present page, I refer to Luminar versions by numbers (1 to 4), starting with the oldest one marked Carl Zeiss. I am not aware of any official Zeiss denomination for the different versions, but a few web sites refer to later versions (version 2 to 4 in my nomenclature) as Luminar II or Luminar 2.
Judging from the number of lenses available at present on auction sites, Zeiss Luminars were the ones most widely sold, with Leitz Photars coming in second, and the remaining brands making up a small portion of the market. In terms of image quality, Zeiss Luminar, Leitz Photar and Macro Nikkor lenses are generally regarded as the best.
Carl Zeiss also produced a few series of Epiluminar (or Epi Luminar) lenses, roughly in the 60's and 70's. These are optically similar to, or identical with, Luminar lenses of the same period, but the optics are mounted in different barrels that do not have a variable aperture. They were meant primarily to be used on microscopes, where a wide aperture is needed to reduce the loss of resolution caused by diffraction. I don't know enough about Epiluminars to discuss them here.
Winkel Zeiss Luminars
There are early Luminars marked Winkel Zeiss on their barrels (the logo is the same sketch of a section of an achromat doublet used by Carl Zeiss, with Winkel placed inside the upper lens element and Zeiss inside the lower one (or sometimes Winkel-Zeiss in the upper part and Göttingen in the lower). The 16 mm f/2.5, 25 mm f/3.5, 40 mm f/4.5 and 63 mm f/4.5 Winkel Zeiss Luminars look identical (except for the engraved logo) to the Carl Zeiss Luminars produced shortly thereafter. Serial numbers are also engraved on the barrel. I have not seen any 100 mm Winkel Zeiss Luminar.
There is a simple reason for the existence of Winkel Zeiss Luminars. For several years, Zeiss became more and more involved in the Winkel firm (originally founded as a separate company), until Winkel became completely absorbed into Zeiss in 1946. Until that time, Winkel continued to produce photomacrographic lenses marked Zeiss-Winkel.
There are also early Winkel Mikroluminar lenses, produced roughly at the same time as Leitz was making their equivalent Tessar and Milar lenses (probably in the 40's and 50's). At least the 100 mm, 50 mm and 26 mm models (the two last ones in chrome-plated barrels) were produced as Winkel-Zeiss Göttingen products.
For a collector, Winkel-Zeiss Luminars and Mikroluminars might be interesting, because probably there are not many of them in circulation. For a user, it is best to seek Zeiss Luminars. Being produced later, they likely have better lens coatings, and consequently a higher contrast and lesser sensitivity to flare. I have only seen pictures of Winkel Zeiss Luminars, and being primarily interested in Zeiss Luminars as a user, I have never actively tried to obtain one of the former.
Luminar 100 mm f/6.3
The Luminar 100 mm f/6.3 is available in at least three versions (which probably are not simultaneous with the versions of other Luminar lenses). This lens, with an optimal reproduction ratio between 0.8x and 8x, actually overlaps the macro photography range, in addition to the photomacrographic one. Reaching 8x with this lens requires a bellows (or stack of extension tubes) roughly 850 mm long, so the maximum practical magnification with this lens is actually around 1.5x to 2x. In this magnification range, there are many lenses that are easier to use (e.g., normal macro lenses, with or without extension rings) and/or perform equally or better (e.g., the 63 mm Luminar, or the 74 mm Zeiss S-Planar). Thus, the Luminar 100 mm does not appear to be especially desirable for use with DSLRs. Many of the specimens for sale on Ebay apparently were either used with Ultraphot photomicroscopes, or mounted on large-format cameras.
Luminar 100 mm Version 1 has a long barrel, a front lens element well recessed within a filter mount and a mounting thread located at the end of a long, cylindrical portion of the barrel that was designed to sleeve into a matching Ultraphot adapter with a thread deeply recessed within a cylindrical tube. This is probably the earliest version of the lens, and may be a similar, or the same, design that I have seen in a 100 mm Winkel Mikroluminar. The mount is said to use a 44 mm x0.75 thread, although this may be incorrect.
Luminar 100 mm Version 2 changed the front of the lens to its modern, flat appearance without a filter mount. The barrel remained long, with a total of four knurled rings (including the aperture ring), and an attachment thread of 33 mm x0.75 .In this version, the threaded attachment is located on a short end of the rear barrel that has a lower diameter than the rest, and screws into a shallow adapter. The front of the lens barrel can be unscrewed, revealing a second attachment thread, and screwed onto the rear of the lens. This allows the lens to be reversed (primarily for use at magnifications below 1x). Also this version was primarily made as an Ultraphot attachment.
Luminar 100 mm Version 3 shortened the barrel considerably. Perhaps the optical formula was also modified. The barrel has only two knurled rings (including the aperture ring). In most specimens of this version, the front knurled ring can be unscrewed for reversing the lens (however, specimens without this feature also seem to exist). Most specimens for sale are of version 3. Although this version is the last for this lens type, it is probably older than versions 3-4 of the other Luminars (see below), because production of this focal length stopped earlier, probably in the 70's. Version 3 of the 100 mm may have been produced also with a fixed Ultraphot mount. Some Version 3 100 mm Luminars are mounted in long Ultraphot adapters that bring the total length of the lens and adapter to the same as in Versions 1-2.
The Zoom Luminar is optimized for magnifications between 2.5x and 5x. It was made both with a fixed Ultraphot attachment (or more precisely, a 43 mm male Zeiss bayonet commonly used in many Zeiss microscope components), and with an unspecified screw thread. This is a very rare lens, and I cannot add much more to this discussion, other than it seems not to be designed for use on bellows or extension rings. I am unaware of different versions.
The Zoom Luminar is not listed in the 1974 Zeiss price list, and I believe it is older than this. Apparently, its production stopped approximately around the time Version 2 Luminars were introduced.
From the point of view of usefulness in modern photomacrography, its zoom mechanism could save some time when many pictures must be taken (especially if this lens is parfocal, which I cannot confirm). However, the zoom ratio is quite small. If time and ease-of-use are important, a Tessovar is a better choice.
Version 1 Luminars
The remaining Luminar lenses have the following focal lengths and maximum apertures. These lenses are especially relevant when discussing different versions, because all focal lengths exist in at least three versions.
16 mm f/2.5
25 mm f/3.5
40 mm f/4.5
40 mm f/4
63 mm f/4.5
Version 1 Luminars seem to be identical to the ones produced with the Winkel Zeiss logo. The tell-tale characteristics of their barrels are:
The labels usually don't say Luminar anywhere, but the 16 mm, 25 mm and 40 mm sometimes have LUMINAR engraved in white on the barrel, at the rear (not in front) of the diaphragm ring. Thus, Zeiss has been making small cosmetic changes during the lifetime of this Luminar version. Most likely, the specimens marked LUMINAR are more modern than the un-marked ones, because the earlier Winkel Zeiss version did not have these markings, while versions 2 and later do have comparable ones (albeit in front of the aperture ring). These specimens with LUMINAR marking may also have an additional label, at the same level, that says Lens made in Germany
The labels in front of the aperture ring usually say Germany (not West Germany). However, there are a few exceptions, which probably were made for the USA market, which say West Germany (at that time, if you tried to send a letter to Germany from the United States, it would be returned to you with a request to specify either West or East).
There are occasional, even stranger specimens of this version, with customer inventory numbers, order numbers, order dates etc. engraved instead of the serial number or other labels.
The focal length, maximum aperture, logo, aperture scale, aperture index and serial number are engraved on the barrel in front of the aperture ring. This data is painted in white, except for the focal length and f/ aperture, which are color-coded as follows:
16 mm: Brown.
25 mm: Orange (sometimes age-darkened to red).
40 mm: Green.
63 mm: Blue.
The Version 1 40 mm has a maximum aperture of f/4.5. Subsequent versions use a completely re-designed optical formula with a maximum aperture of f/4. The front and rear elements of the newer versions of this lens are visibly larger, and the rear of the lens in Versions 2 and 3 projects about 5 mm behind the threaded mount (picture at the left), while it is recessed within the threaded mount in Version 1. These are the largest changes among versions of the same Luminar lens that I am aware of. There seems to be no official explanation of this redesign, and only a comparative side-by-side test of versions of this lens might provide an answer. Until then, if you intend to use this lens for photography, I would recommend that you buy a Version 2 or 3 of this lens, and avoid Version 1 (which is exactly what I did).
My test of a Version 1 and Version 3 of the Luminar 63 mm give the Version 3 a slight performance edge in several respects, but it is questionable whether this matters in practical use. It is also evident that the optical formula was re-calculated between these versions (probably between Version 1 and Version 2, although I cannot be sure until I get to test this version as well).
Version 1 Luminars have shiny, polished, mirror-like aperture blades. They do not appear to be blackened, and simply reflect the incoming light in a very obvious way.
Version 1 Luminars seem to have been manufactured mainly in the 60's.
Version 2 Luminars
This version has similar engravings and color-coding as Version 1, but differs in the following respects:
The 16 mm is mounted onto an extension ring about 15 mm long, which has no markings. The 25 mm is mounted onto a 10 mm long extension ring, also with no markings. Without these extension rings, these lenses have barrels exactly as long as the 40 mm (e.g., see picture below).
The lens barrel has only one knurled ring (i.e., the aperture ring).
The lens aperture is no longer indicated as f/ factor, but instead as a numerical aperture value only (i.e., like on microscope objectives).
The barrel of the 25 mm in this version seems to be much longer than in Version 1 (see also pictures of a 25 mm Version 4, below). However, the last 10 mm of the barrel consist of an extension tube with male and female RMS threads at opposite ends, which can be unscrewed. This ring has no markings. Without this, the lens barrel is quite similar to a 40 mm Version 2 and later (see above pictures). Curiously, all 25 mm Version 2 and later I have seen have this extension ring, but no 40 mm Version 2 or later I am aware of has the same extension ring, in spite of the projecting rear elements of the latter lens. The Version 2 (and later) 16mm was similarly sold mounted on a 20 mm extension ring, and its barrel without this tube, as seen from the side, also has the same size of the two lenses mentioned above.
It is possible that these extension tubes were added for a specific reason, i.e., with the 40 mm, 25 mm and 16 mm mounted on a revolving microscope nosepiece, the tubes do reduce the amount of refocusing necessary when switching between these lenses. Since large Zeiss photomicroscopes like the Ultraphot and the Universal/Photomicroscope series can indeed be used with Luminar lenses (by removing the condenser carrier and sliding the object table to a lower position), it seems likely that this was the original thought behind the extension tubes. The 63 mm and 100 mm, on the other hand, although usable on these microscopes, have working distances too high to allow them to be used together with the shorter focal lengths without extensive refocusing, and the latter lenses would require excessively long extension tubes to avoid this problem. Zeiss also sold similar extension tubes with RMS threads, meant to be used with microscope objectives. These tubes have a larger external diameter and were available in a few different lengths.
The aperture blades of Version 2 Luminars are polished and shiny, like those of Version 1.
Version 2 Luminars probably were manufactured (roughly) in the 70's and early
Version 3 Luminars
The barrel geometry and, as far as I can tell, optical formulas remain the same as in Version 2. Possibly, the lens coatings are better, but I can tell no difference by comparing pictures taken with Version 2 and Version 3 lenses. There are very small differences in performance between Version 1 and Version 3 of the Luminar 63 mm, and possibly other models of these versions. The 16 mm and 25 mm are still mounted on extension rings. The changes seem to be only or mainly cosmetic:
Three round colored dots distributed around the barrel are used to indicate the focal length, instead of colored labels. The same color-coding is used as in Versions 2 and 1.
All writings on the barrel are now white.
The Carl Zeiss logo is gone.
The Zeiss name (without Carl) is printed in a fat font.
The label says West Germany.
f/ factors have come back on the labels, and are printed together with numerical apertures. Oddly, the label of the Version 3 40 mm says 40 mm 1:4/A 0,13, while version 2 reports the numerical aperture as 0,12. The N.A. of the 63 mm is also marked 0,11 in version 3 and 0,1 in Version 2.
As far as I can tell, the labels and colored dots are always silk-screened onto the labels, not engraved. This means that these markings are vulnerable to wear and skin oils, and in fact they have been scraped away or have detached in some specimens I have seen. However, the aperture scale in these lenses (at the rear of the aperture ring) is instead engraved.
The aperture blades of Version 3 Luminars are black with a matte surface. It is possible that this reduces the risk of flare by preventing light reflected from the blades being again reflected into the aperture by the surfaces of the front element(s).
Version 3 Luminars probably were manufactured in the 80's.
Version 4 Luminars - The last dinosaur?
According to Bracegirdle (Bracegirdle, B., 1995: Scientific photomacrography, Royal Microscopical Society/Bios Scientific publishers, Oxford), the Luminar 25 mm f/3.5 was still sold in 1994, while all other focal lengths had been discontinued. This, coupled with an odd cosmetic difference in specimens of this lens, suggests that a Version 4 does indeed exist.
The specimen of Luminar 25 mm shown above has engraved labels and engraved color dots. In fact, the dots show clear concentric markings left by the milling engraver, and especially the Zeiss name is deeply recessed (see detail; in this specimen the milling machine left fine burs in relief inside some of the ZEISS letters). It is possible that Zeiss went back to a conservative type of marking after being plagued by poor durability of the silk-screenings on optical and microscope equipment of the 80's (which indeed tended to fall off after only moderate use). Except for the engravings, and possibly for the lens coatings, it is identical to Version 3 Luminars. I am aware of at least one more specimen of this lens and version, identical in all details to the one illustrated here, so this is not a one-of-a-kind fluke.
Note also the 10 mm extension ring mounted at the rear of the lens barrel. This extension ring seems to be always present in 25 mm Version 2-4 Luminars.
The aperture blades are matte black, like in Version 3.
I also know for a fact that there are some, exceedingly rare, Luminar 63 mm with engraved color
dots and labels. These specimens must belong to Version 4, like the 25 mm illustrated above. On the other hand, so far I have seen no 16 mm or 40 mm Luminars with these characteristics. All those I have seen have silk-screened color dots and labels, and therefore are Version 3 Luminars.
There is still a chance that I might be wrong about version 4 Luminars, or that the story is more complicated than I think, because I have seen pictures of just one 25 mm which appears to have silk-screened labels but engraved dots. At the same time, I fail to see why Zeiss would have produced sets of Luminars that mixed silk-screened lenses with engraved ones. For the moment, I regard the existence of a Version 4 of Luminars as likely, and distinct from Version 3.
The differences among Luminar versions discussed and illustrated in this page are summarized in the following table. Unique characteristics of each version are highlighted in red. In addition, the shape of the aperture ring reliably differentiates series 1-2 from 3-4 (see above).
"Screwdriver" slots in front ring: yes
number of knurled rings: 2 (but 40 mm: 1)
labels engraved or silk-screened: engraved
aperture marked in: f:ratio
logo: CARL ZEISS
country marked as: Germany (but sometimes West Germany or other things)
color coding used on: focal length and aperture
label says LUMINAR: sometimes, at rear of aperture ring
aperture blades: shiny
extension ring: no
"Screwdriver" slots in front ring: no
number of knurled rings: 1
labels engraved or silk-screened: engraved
aperture marked in: n. aperture
logo: CARL ZEISS
country marked as: West Germany
color coding used on: focal length, LUMINAR and aperture
label says LUMINAR: yes, in front of aperture ring
aperture blades: shiny
extension ring: on 16 and 25 mm only
"Screwdriver" slots in front ring: no
number of knurled rings: 1
labels engraved or silk-screened: silk-screened (but aperture scale is engraved)