The pros and cons of third-party lenses

March 7, 2024 / spqr / Leave a comment

Once you have chosen a particular camera, (and manufacturer) it is time to think about lenses. Most people will buy a camera with some sort of kit lens attached, usually because it is cheaper. Others buy just the camera body, and outfit it accordingly, but it often a vast maw of choices. Lens choice is usually foremost about need, and ultimately focal length. What are you going to be shooting – portraits, landscapes, architecture? Then it becomes a balancing act of lens characteristics. If you choose, say a 35mm lens on an APS-C sensor, so 50mm equivalent, then it’s about things like size/weight (e.g. for travelling), weatherproofing, maximum aperture, build (metal/plastic), and of course cost.

This leads us to the question some people end up pondering – do you buy a lens from the camera manufacturer or a third-party? Firstly, let’s consider each type of lens. Lenses produced by the camera manufacturer are often considered the creme-de-la-creme. They are designed from the bottom up, as integral components of the system. Quality and compatibility are the reasons why professional photographers stick with first-party lenses. These particular lenses are made specifically for the camera brands that they carry, so they are not compatible with any other manufacturers or brands.

Third-party lenses on the other hand, are often designed by lens companies from the perspective of creating a variety of lenses that will fit cameras from multiple manufacturers with the simple change of a mount (and tweaking some other specs). For example Sigma produces a 28mm f/1.4 lens that is available in Canon (EF), Nikon (F), Sony (E), and Leica (L) mounts. As with many manufactured items there are different levels of third-party lens manufacturers, from precision, high-priced lenses to mass-produced budget-oriented lenses. Third-party lenses can also be differentiated into long-established ”old-school”, and newer lens manufacturers. Voigtländer and Zeiss are good examples of well-established 3rd party lens makers who produce higher-end “boutique” glass.

*Manufacturer versus third-party lenses*

So why choose a 3rd party lens? There are many reasons. I suspect most people go that route because of the general affordability of the lenses. This also makes sense if someone wants to experiment with a particular lens, but doesn’t want to pay a small fortune. Affordability is often perceived as a sign that the lenses are inferior from the viewpoint of capabilities or build, but this isn’t always the case. Sometimes the lower price is a factor of trades-offs: manual focus instead of auto-focus capabilities, polycarbonate lens body instead of metal, etc. Some third-party lenses offer functionalities such as large apertures, e.g. f/1.0, or a smaller, lighter build, or even a lens not offered by a camera manufacturer, e.g. fish-eye lenses. For example the shortest focal length produced by Fuji is 8mm f/3.5 (12mm eq.), however it is US$800. An alternative for the photographer wishing to experiment with fish-eye lenses is the Tokina SZ 8mm f/2.8 (US$300).

What about disadvantages? Well the flip-side of 3rd party lenses is the lower-cost is that the lenses are sometimes optimized for lower cost. There may be some manufacturers that sacrifice the quality of materials used in lens manufacturing, and hence lens durability for a lower price. There is also the chance that the lens will not be 100% compatible with every one of the cameras it fits on. This goes back to the materials/build sacrifices made in construction. Another “disadvantage” for some is that many third-party lenses is manual focus. This is partially because it is cheaper and easier to produce a lens without focusing mechanisms, and electronic connections to the camera. However manual focusing is not a huge issue, because of functions built-into many cameras these days which assist with manual focusing, e.g. focus-peaking.

Actually the main problem in choosing lenses from 3rd-party manufacturers is differentiating between them. Because apart from the price differential, the specs of many lenses look quite similar. Below are five third-party 12mm lenses for the Fuji-X system (Fuji does not make a 12mm, the closest is a 14mm f2.8).

	Aperture range	Elements/group	Weight	Barrel material	Cost (US$)
Zeiss Touit	f/2.8 − 22	11/8	260g	metal	$999
Rokinson	f/2.0 − 22	12/10	260g	metal + plastic	$399
Meike	f/2.8 − 22	12/10	326g	metal	$230
Pergear	f/2.0 − 22	12/9	300g	metal	$165
7Artisans	f/2.8 − 16	8/10	265g	metal	$149

Table: The gamut of 12mm lenses for Fuji-X

So when you get to choosing a lens, you may be swayed by the extremely reasonable prices of some of the 3rd party lenses. So what to do? Well the first thing to do is to find a website that maintains an updated list of lenses for a particular system. I’ll give examples of Fuji-X, because that has become my core system. Here is a good list from Alik Griffin. Third party lens manufacturers can be separated based partially on the quality of optics (and let’s face it, cost). At the end of the day, the actual lens you choose will depend on budget and individual requirements. If you decide to buy a third-party lens, make sure you do a good amount of research into the lens. Check out independent reviews from photographers, both professional and hobbiest, that have used the lens.

The Eyes of Eagles (and why Zeiss used them to advertise its lenses)

July 25, 2023 / spqr / Leave a comment

It was Zeiss who came up with the “the eagle eye of your camera” slogan in the 1930s to advertise their lenses (or in German “Das Adlerauge Ihrer Kamera” – eagle eye being Adlerauge) [1]. Of course they were mostly talking about the Tessar series of lenses.

“The objective should be as the eagle’s eye, whose acuity is proverbial. Where its glance falls, every finest detail is laid bare. Just as the wonderful acuity of the eagle’s eye has its origin, partly in the sharpness of the image produced by its cornea and lens, and partly in the ability of the retina – far exceeding that of man’s vision – to resolve and comprehend the finest details of this delicate image, so, for efficiency, must the camera be provided on the one hand with a ‘retina’ (the plate or film) of the highest resolving power – a fine grain emulsion – and on the other hand with an objective which can produce the needle sharp picture of the eagle’s lens and cornea.”
The Eagle Eye of your Camera (1932)

Zeiss took great lengths to use this simile to describe their lenses. A lens must have the sharpness of an eagle’s eye, and the ability to admit a large amount of light – sharpness and rapidity over a wide field of view – the Zeiss Tessar. While Leica named their lenses to indicate their widest aperture, Zeiss instead opted to name their lenses for the design used. Indeed the Tessar came in numerous focal length/aperture combinations, from a 3¾cm f/2.8 to a 60cm f/6.3.

*Zeiss “Eagle Eye” advertising in the 1930s*

The Tessar is an unsymmetrical system of lenses : 7 different curvatures, 4 types of glass, 4 lens thicknesses, 2 air separations, i.e. 17 elements which can be varied. Zeiss went to great lengths to disseminate the message about Tessar lenses:

sharp, flare-free definition
great rapidity (allowing short instantaneous exposures)
exceptional freedom from distortion (obviating any objectionable curvature)
good colour correction
compact design (so that light falling off near the edge is reduced to a minimum)
sufficient separation of the components of the lens (to allow a between lens shutter)
the use of types of glass as free as possible of colour
reduction to the minimum of the number of lenses, and particularly of glass-air surfaces

*“It must have the sharpness of the eagle’s eye”*

It is then not surprising that Zeiss choose to compare the lens to an eagle’s eye. The eagle is considered to be the pinnacle of visual evolution. They can see prey from a distance – it is said they can see a rabbit in a field while soaring at 10,000 feet (1.9 miles or 3km). It was Aristotle (in 350BCE) who in his manuscript “Aristotle, History of Animals” pointed out that “the eagle is very sharp-sighted”. The problem however is that it’s not really possible to compare a simple lens against the eye of a living organism. Zeiss was really comparing the lens of an eagle’s eye against the Tessar, or rather the Tessar and the human eye behind it, because the camera lens is just a part of the equation of analog picture taking. So how does an eagle eye compare to a human one?

It’s kind of hard to really compare eyes from different species because they are all designed to do different things. In all likelihood, human eyes have evolved over time as our environment changed. In birds, unlike humans, each eye looks outwards at a differing scene, and the overlap of the visual field of both eyes, i.e. the binocular region, is relatively small. This is typically less than 60° in birds, versus 120° in humans, and can be as narrow as 5-10° in some species. Because of this a birds total visual field is quite extensive, with just a narrow blind region behind the head. Eagle’s have a highly developed sense of sight which allows them to easily spot prey. They have 20/5 vision compared to the average human who has 20/20 vision. This means they can see things at 20’ away that humans only have the ability to see at 5’. They have fixed eye sockets, angled 30° from the mid-line of their face, giving them a 340° view. Many also have violet-sensitive visual systems, i.e. the ability to see ultraviolet light and detect more colours than human eyes can.

A *Golden eagle, and a cross-section of an eagle’s eye*

The first thing to consider may be the size of the eye. We will pick one eagle to compare against human vision, and the best option is the (European) Golden Eagle, because it is quite common in Germany. The average weight of a Golden Eagle is 6.1kg, versus the average weight of a European (human) at 70.8kg. If we work on the principle that an eagle’s eye is similar in weight to a human eye (ca. 7.5g) then an eagle’s eye would comprise 0.12% of its body weight, versus 0.01% of a human. So for the human’s eye to be equivalent in mass based on eye:body weight ration, it would need to be 85g. But this is really an anecdotal comparison, the bigger picture lies with the construction of the eye.

One of the reasons birds of prey have such incredible eye-sight is the fact that their deeper fovea allows them to accommodate a greater number of photoreceptors and cones. The central fovea in an eagle’s eye has 1 million cones per square millimetre, compared to 200,000 in a human eye. One way that eagles do this is by having increased resolution. This is achieved by have reduced space between their photoreceptors. Due to the physics of light, the absolute minimum separation between cones for an eye to function correctly is 2µm (0.002mm). As the space between the photoreceptors decreases, so too does the minimum size of the detail.

The other thing of relevance is that while humans have one fovea, eagles generally have two – a central fovea used for hunting (cone separation 2µm, versus human cone separation of 3µm), and a secondary fovea which provides a high resolution field of view to the side of their head. So like a camera sensor, more cones means better resolution. In context Robert Shlaer [2] suggested that the resolution of a Golden eagle’s eye may be anywhere from 2.4 to 2.9 times that of a human, with the Martial Eagle somewhere between 3.0 and 3.6 times. The spatial resolution of a Wedge-Tailed eagle is between 138-142 cycles per degree [3], while that of a human is a mere 60. Their foveae are also distinctly shaped, deep and convex, as opposed to the rounded and shallow single fovea of human eyes. In a 1978 article for the scientific journal Nature, Snyder and Miller [4] proposed that the unique shape of foveae found in some birds of prey may act like a telephoto lens, magnifying their vision, which is perhaps why these feathered predators can spot food from so far in the sky. Like humans, eagles can change the shape of their lens, however in addition they can also change the shape of their corneas. This allows them more precise focusing and accommodation than humans.

But Zeiss themselves harked on the limitations of the simile: The fact that an eagle can quickly turn its head to allow for viewing in any direction; the fact that the retina is curved, not flat. From the perspective of resolution the ads were true to form, however the other aspects of the an eagle’s vision did not ring true. Yes, telephoto lenses based on the Tessar design could certainly see further than a human, and given the right lens and film could see into the violet spectrum, but Zeiss’s claim was really more about finding a way to describe it’s lenses in a provoking manner, one which would ultimately sell lenses.

Zeiss versus Zeiss : the trademark dispute

July 5, 2023June 22, 2025 / spqr / Leave a comment

As cooperation deteriorated, and finally terminated in 1953, it was inevitable that eventually there were some issues with trademarks between the two Zeiss’s. I mean they were on different sides of the Iron Curtain. The East German Carl Zeiss company did not own all the rights to some of the names and brands. This would likely have been fine had they just been sold within the eastern-bloc countries, however many were made to be exported to the west (which is really somewhat ironic) – lenses were developed to sell in the West to produce hard currency. They achieved this at the beginning by resurrecting pre-war designs. Political influence over East Germany did not have any influence in how products were manufactured.

*Zeiss vs. Zeiss branding over the years*

In February 1954 Zeiss in Heidenheim fired the first shots in what would eventually become a worldwide litigation. They obtained an injunction in the District Court of Goettingen to prevent the continued sale of Jena-made, Zeiss-marked goods [1]. In April Zeiss Jena countered in West Germany by seeking an injunction and an order registering the Zeiss marks in West Germany in its name. That action was dismissed in 1960 when the West German Supreme Court ruled that there was no one in the Soviet Zone having capacity to represent the Zeiss Foundation.

In the same year Zeiss Heidenheim brought action against the Zeiss Jena to prevent them from using the Zeiss name and trademarks anywhere in the world. The Supreme Court of the Federal German Republic determined that the Heidenheim firm was entitled to exclusive use of the Zeiss name and trademarks in West Germany and West Berlin [1]. Interestingly, a CIA report from 1954 [2] suggests that should the naming issues take an “unfavourable” turn for VEB CZJ, then the plan was to change its name to VEB Ernst Abbe Werk (which they obviously never did).

There was also a long court battle in the US over who owned the rights to the Zeiss name. The litigation commenced on February 14, 1962, filed by Carl Zeiss Foundation and Zeiss Ikon AG against VEB Carl Zeiss Jena and its US distributors [1] (Carl Zeiss Stiftung v. VEB Carl Zeiss Jena). The case went to discovery from 1963-1967 and finally to trial in November 1967. On November 7, 1968, the court found in favour of the plaintiffs, deciding that the US trademarks “Zeiss”, “Zeiss Ikon”, and “Carl Zeiss Jena”, were the property of the Zeiss firm located in West Germany. As to the legitimacy of this? The courts found that the original “Stiftung” ceased to exist in Jena when it had been stripped of its assets. The Stiftung’s domicile was then changed from Jena to Heidenheim. It was not until 1971 [3] that the US Supreme Court finally settled the case of Carl Zeiss vs. VEB Carl Zeiss Jena, after a long 9½ year battle for control of the “Zeiss” trademark, siding with Heidenheim.

*Examples of Carl Zeiss Jena lens markings over the years.*

After this, Carl Zeiss marketed their lenses as “Carl Zeiss” exclusively in the United States, whereas Carl Zeiss Jena exported their lenses to the US with the marking “aus Jena”, or sometimes “JENOPTIK”, or even “JENOPTIK JENA”. The branding on these lenses was changed: “T” instead of Tessar, “B” for Biotar, “Bm” for Biometar, “S” for Sonnar, “F” for Flektogon, etc. in order not to infringe on the copyright. Therefore a lens might be labelled “Carl Zeiss Jena s”, or “aus Jena s”, and be exactly the same lens. It really depended on where the lenses were sold.

In the Eastern-bloc countries, CZJ could use the name “Carl Zeiss”. Carl Zeiss Oberkochen was not allowed to use “Zeiss” by itself, and instead used the name “Opton” or “Zeiss-Opton”.
In some western countries – namely West Germany, Italy, Greece, Holland, Belgium, Luxembourg, and Austria – CZO was allowed to use the name “Carl Zeiss”. CZJ chose to use the name “aus Jena” in the case of lenses.
The rest of the world, i.e. Commonwealth countries like England and Canada, Switzerland, Japan, both companies could use the name “Carl Zeiss”, but only if there was an indicator of origin. For example CZO used “Carl Zeiss West Germany”, and CZJ used “Carl Zeiss Jena” or the term DDR somewhere.

*Examples of Carl Zeiss Opton lens markings over the years.*

Of course it is also easy to identify a lens if it is marked with DDR. Some lenses were made in only East or West Germany, while others had names which continued to be shared.

East German only lenses: Biometar (a modified Planar), Flektogon (similar to Distagon), Flexon, Pancolar
West German only lenses: Distagon
Shared lenses: Hologon, Biogon, Biotar, Magnar, Planar, Protar, Sonnar, Tessar, Topogon, Triotar

Zeiss versus Zeiss : the postwar split

June 13, 2023June 22, 2025 / spqr / Leave a comment

One of the things that gets very confusing for some people is differentiating between Zeiss lenses from East and West Germany. First, let’s look at the backstory. Prior to World War II, Carl Zeiss Jena had been one of the largest suppliers of optical goods in the world. Note that Carl Zeiss was an optical company and different to Zeiss Ikon, which was a camera company formed in 1926 from the merger of four camera makers: Contessa-Nettel, Ernemann, Goerz and Ica. Both were members of the Carl Zeiss Foundation.

During the war, Jena had been pounded by allied bombing – the British bombed the Zeiss works on 27 May 1943, and the Americans repeated this twice in 1945. Mind you, there was not enough damage to put the factories out of commission but enough to slow production. Jena was captured by the American 80th Infantry Division on April 13th, 1945, and would remain in US control for two months before withdrawing in favour of the Soviet forces. As Americans departed, they took with them 122 key personnel from Jena to Heidenheim in the US zone of occupation (the personnel were from Carl Zeiss and Schott). At the conclusion of hostilities in 1945, Germany was split into differing zones, and as Jena was in the German state of Thuringia, it came under Soviet control (based on the Yalta Conference agreement).

A New York Times article in September 1946 suggested that the Russians were taking US$3,000,000 worth of finished products monthly for reparations [1]. At this stage there was very little in the way of dismantling equipment to ship back to Russia. In fact an earlier NYTimes article [2], suggested Russian occupation authorities had actually stimulated production at the Zeiss plants to pre-war levels, in order to facilitate reparations. It should be noted that the Zeiss plant produced more than just photographic optics – it also produced microscopes, medical and surgical instruments, ophthalmic instruments, geodetic instruments, electron microscopes, binoculars, etc., and military items [3].

*The bombing damage to the Zeiss Jena plant*

By 22 October 1946, the Soviet occupation authorities began dismantling the Zeiss plant [3] as war reparation payments agreed upon in the Potsdam Agreement. This was known as Operation Osoaviakhim, and involved many industries across Germany. It resulted in the removal of 93% of Zeiss’ equipment (including raw material, pipes, boilers, sanitary installations, etc), and 275 Zeiss specialists [4] deported to various locations in the USSR (approximately 90% of those deported would return to Jena in 1952). The taking of war “booty” was of course entirely legitimate, yet as Peter Nettl put it in a 1951 article, “Like a child long deprived of chocolate, the first Soviet ‘dismantlers’ flung themselves on all the available tidbits” [5].

A US intelligence report from July 1947 described the status of the Zeiss works at Jena [6]. In it they suggest that optical and photographic production had been least affected by the dismantling, with the plant producing lenses for the Soviets (Tessar 5cm f/3.5). The dismantling program had been completed by April 1947 [7], after which the Soviet High Command turned the plant over to the Germans, who re-established the plant. About 1000 machines remained at Jena after the dismantling, allowing for the continued production of eye glasses, camera lenses, medical glass and measuring instruments [8]. There was every hope at this time (at least from the West German side of things), that this was a temporary situation and that in 3-5 years Heidenheim staff would move back to Jena [6].

In June 1948, the Zeiss Jena plants were expropriated by the Land Expropriation Commission [9] and transferred to state ownership, becoming known as “VEB Carl Zeiss Jena”. In the American zone, Zeiss was reborn as “Opton Optische Werke Oberkochen GmbH” in 1946, becoming “Zeiss-Opton Optische Werke Oberkochen GmbH” in 1947, and Carl Zeiss in 1951. They had very little except the relocated personnel and supposedly a quantity of Zeiss documents. In 1949 Germany officially split into East Germany (Deutsche Demokratische Republik) and West Germany (Bundesrepublik Deutschland). Between 1948 and 1953 the two firms cooperated commercially with one another, after which cooperation deteriorated as the East German regime tightened control on VEB.

Like Zeiss, Zeiss Ikon (Dresden), best known for its Contax camera, also split in 1948. In the west, it was reformed into Zeiss Ikon AG Stuttgart. In the mid 1960s it merged with Voigtländer. It followed the Contax rangefinder line releasing the Contax IIa and IIIa cameras in the early 1950s. In the east, Zeiss Ikon became state owned, known as VEB Zeiss Ikon Dresden (ZID). ZID may be best known for its advanced SLR model, the Contax S, introduced in 1948.

Ultrafast lenses – the Zeiss Planar 50mm f/0.7

July 8, 2022January 3, 2025 / spqr / Leave a comment

The quintessential vintage ultra-fast camera lens is the Zeiss Planar 50mm f/0.7. It was developed in 1961 for a specific purpose, namely to photograph the dark side of the moon during the NASA Apollo lunar missions. Only 10 lenses were built, one was kept by Zeiss, 6 went to NASA and 3 were sold to director Stanley Kubrick. Kubrick used the lenses to film scenes lit only by candlelight in the movie “Barry Lyndon” (1975).

There is a similarity, at least in the double-Gauss optical design – it is essentially a Gauss front with two doublets glued together and a rear group which functioned as a condenser. (copies of optical diagram). The 50mm f/0.7 Planar was designed by Dr. Erhard Glatzel (1925-2002) and Hans Sauer. It is supposedly based on an f/0.8 lens designed by Maximilian Herzberger (1900-1982) for Kodak in 1937. Looking at the two schematics, they look quite similar. The idea is to take the 70mm f/1, and by adding a condenser, brute-force the lens into a 50mm f/0.7. The condenser actually shortens the focal length and condenses the light – in reality adding a ×0.7 teleconverter that gives 1 f-stop.

But this lens has an interesting backstory. According to Marco Cavina, who has done a lot of research into the origin of this lens (and others), the design of this lens was derived at least in part from lenses designed for the German war effort. During WW2, Zeiss Jena designed a series of lenses for infrared devices to be used for night vision in various weapons systems. One such lens was the Zeiss UR-Objektiv 70mm f/1.0. The design documents were apparently recovered during Operation Paperclip from the Zeiss Jena factory before the factory was occupied by the Soviets and then provided to the new Zeiss Oberkochen.

The design went through four prototypes before achieving the final configuration [1]. The final scheme was optimized on an IBM 7090, which had been in operation since the late 1950s. The lenses were used on a modified Hasselblad camera.

Glatzel, E., “New developments in the field of photographic objectives”, British Journal of Photography, 117, pp.426-443 (1970)
https://wlpa.auction2000.online/auk/w.object?inC=WLPA&inA=20200729_1055&inO=329

Crafting Pixels

Vintage lenses, photography and digital imagery

Zeiss

The pros and cons of third-party lenses

The Eyes of Eagles (and why Zeiss used them to advertise its lenses)

Further reading:

Zeiss versus Zeiss : the trademark dispute

Further reading:

Zeiss versus Zeiss : the postwar split

Further reading:

Ultrafast lenses – the Zeiss Planar 50mm f/0.7

Further reading: