The Rolleiflex Twin Lens Reflex Camera was basically an instant success from the time the first model reached the market in 1929. After producing many different models with continual upgrades, in December 1949, Franke & Heidecke introduced its first f/2.8 taking lens into a Rolleiflex, namely the 80mm Tessar 2.8 (of pre-war manufacture). The camera that featured this lens is known as the Rolleiflex 2.8 A model. Only sold in the US, this camera with its fast Tessar lens was poorly recieved and was frequently cited as being soft. One source* states that half of these cameras were returned to Franke & Heidecke as part of a recall. Supposedly, the construction of these Tessars was faulty and the Rolleiflex 2.8 A was a commercial flop for Franke & Heidecke which resulted in the creation of the Rolleiflex 2.8 B camera (Feb. 1952) with a new lens; the 80mm f/2.8 Zeiss Biometar constructed with 5 elements. Again, this model was only sold in the US with a mere 1,250 models produced (versus 9,870 model 2.8 A cameras) given issues with post war supplies. While the Biometar produced much better results than the Tessar 2.8, given the tiny production, it wasn't until Franke & Heidecke brought to market the Rolleiflex 2.8 C in December of 1952 with a Schneider Xenotar 5 element lens, that Rollei proved it could produce a f/2.8 TLR that could compete with the resolution of their f/3.5 models while providing a lens speed advantage.
Shortly after the "C" model came to market, in May of 1953*, Modern Photography magazine published the following article by Arthur Kramer:
The New Rollei. How Good is the New $385 Model 2.8C
"The camera's most important feature is its new 80mm, air-spaced five-element f/2.8 Schneider Xenotar lens. The f/2.8 lens on a previous model was a four-element objective [80mm f/2.8 Tessar on the Rolleiflex 2.8A] which often gave trouble when used wide open. The makers of the Rolleiflex claim this trouble has been eliminated in the Xenotar lens. Optical and practical tests (which we will get to later) indicated that this was true - at least on the cameras tested....
Finally we get to the most important of all the improvements - the lens. This is not the first f/2.8 lens ever put on a 2 1/4 x 2 1/4 Rollei. Many photographers who have used or tested the previous f/2.8 model, which this new camera supersedes, felt that the definition was not up to their acceptable standards. Wide aperture lenses which must cover comparatively large film areas are often notoriously poor in edge definition at full aperture. Practically all Automatic Rolleiflexes have up to this time been supplied with four element Tessar or Xenar f/3.5 or Tessar f/2.8 lenses. The new Xenotar is a five-element lens of the air-spaced type. It was not until the advent of modern optical coatings that the full advantage of such a design could be exploited.
The camera was taken to a well-equipped optical laboratory and placed on an optical bench. The lens appeared to be free of astigmatism. It showed no shift of focus when stopped down. There seemed to be the faintest trace of flare at f/2.8 but this disappeared when the diaphragm was stopped down to about f/3, a definite improvement in this respect to what we had previously seen in other lenses of similar focal length and aperture. The definition at the edges was far above that of the old four-element f/2.8. This individual Xenotar lens looked excellent in bench tests, but that did not guarantee excellent pictures. Only extensive tests on actual film could tell about that….
The camera was also checked for lens, film, and ground glass alignment. Then it was ready for the film tests. An f/3.5 Rollei of known image quality was used as a control unit The first test was made on a cross-lit brick wall A series of shots was taken at various distances and apertures with both cameras. Negatives were carefully enlarged to about 30x30 inches and examined over the entire field. Results showed that the Xenotar f/2.8 lens wide open was equal in most respects to the f/3.5 lens wide open. It did not noticeably lose definition when stopped down to f/22. A second Xenotar tested actually had better definition at f/2.8 than the older type lens had at f/3.5! The tests were repeated on various objects and at varied distances with the same result. Twenty rolls or film were used on a variety of subjects. Results were consistently good.”
* Most online sources of this article incorrectly date this article to May 1952 but its actually May 1953
The model C with a Xenotar lens would be made until 1955. In 1954, Rollei also produced the model C with a Zeiss Planar lens of 5 elements. This would be the first appearence of the famous Rolleiflex 2.8 Planar lens. All in all, over 30,000 model C cameras were produced; more with Xenotars than Planars given their later appearence in the production run.
Rollei's next 2.8 camera was the model "D" produced in 1955. Also, produced with either a Xenotar or Planar 2.8 taking lens, just over 20,000 of these cameras were made. In general, Rollei priced their cameras with Xenotar lenses as slightly less expensive than those featuring Planar lenses.
In 1956, Rollei brought out the model "E" 2.8 cameras - yet again making these available with either a Xenotar or Planar 2.8 taking lens. By 1960, over 45,000 model E cameras were made. Also in 1956, Rollei began producing new f/3.5 model cameras featuring either the 5 element Planar lens or 5 element Xenotar lens - slower versions of their bigger sister f/2.8 lenses. These models are known as the Rolleiflex 3.5 E cameras.
All of these exciting improvements to the Rolleiflex line further solidified their position as king of the Twin Lens Reflex cameras. Inevitably, this led to questions as to which Rolleiflex cameras performed better - the 2.8 or 3.5 cameras ?
In May of 1956, Modern Photography published an article comparing the new 5 element Xenotar on the Rolleiflex 3.5E compared to older Rolleiflex models with 4 element Tessar lenses.
Are the new Rolleis Really Better?
"Now lets take a look at that five element f/3.5 lens. It's no secret that there was a cry from professional photographers for a Rolleiflex with an f/2.8 lens and that these camera enthusiasts only got what they wanted when a five element optical system was developed.
With a maximum f/3.5 aperture in 75mm focal lengths, the story has been quite different. The four element Zeiss Tessar and Schneider Xenar 75mm f/3.5 lenses have long been standards of excellence for Rolleis and many other cameras. What more can the new Xenotar five element offer? For all but the most persnickety professional, a good Xenar or Tessar will do nicely. Testing the new Xenotar against a good example of a Schneider Xenar, the resulting picture definition with both lenses was almost identical. This is not to disparage the new Xenotar but rather point out that a good four element Xenar or Tessar can be a very good lens indeed. Perhaps the Xenotar proved a shade sharper in the corners at full aperture than the Xenar. However, in actual photographic practice we doubt that this difference would be perceptible. Xenar or Xenotar? They're both fine lenses."
In 1957, more interesting comparions were done by Modern Photography;
Great Cameras? Fact or Fiction Rolleis have always had a great reputation. Do they still deserve it? "Which Lens is Best? Four or Five Element, F/2.8 or F/3.5
A. 80mm f/2.8 Zeiss Planar is a five-element alternative to the Xenotar on the Rolleiflex 2.8E. Although the line-up of optical elements is rather different from the Xenotar, performance is similar. It produces excellent definition to the corners of the negative, even at full aperture.
B. 80mm f/2.8 Schneider Xenotar has five elements and can be had on the Rolleiflex 2.8E. In extensive tests with this lens Modern found it extremely sharp in overall definition. The five-element 80mm f/2.8 lenses are considerable improvements over the discontinued four-element 80mm f/2.8
Tessars once available on the Rolleiflex 2.8.
C. 75mm f/3.5 Zeiss Planar is a five element alternative to the Xenotar on the Rolleiflex 3.5. It shows excellent definition even at full aperture.
D. 75mm f/3.5 Schneider Xenotar with five elements has now completely replaced the four element Xenar on all Rolleiflexes. Differences in definition between the discontinued four-element Xenar and this five-element Xenotar at f/3.5 are almost impossible to see, even with great magnification of the negative corners. Definition, to say the least, is excellent in the 75mm f/3.5 Xenotar.
E. 75mm and 60mm Schneider Xenar are available on the Rolleicord Va and Rolleiflex 4x4 respectively. The Xenar design is of a traditional four-element Tessar-type construction. Performance at such moderate aperture (f/3.5) and focal length (75mm) is excellent compared with that of the 75mm f/3.5 five-element Xenotars and Planars."