The Zeiss Ikon Contax Camera Repair Website. Servicing A Zeiss Contarex Body. A Couple of Contarex Warnings. Lenses This section applies only to the Conta. REX lenses and DOES NOT apply to the Contax I, II or III, IIa or IIIa Rangefinder cameras nor does it apply to the Conta. FLEX line of 3. 5mm SLR cameras. The only exceptions to this Contarex lens warning are the Contarex 2. Olympia Sonnar, the 1. Olympia Sonnar, the two Zoom lenses, the 3. Schneider, the Bellows Tessar, and the 2. Biogon. All other Contarex lenses are the object of the following warning section. Zenza Bronica ETRSi camera specifications. The Bronica ETRSi was manufactured from 1989 to 2004. The first model, the ETR, was released in 1976. Pic_3_CZJ_Contax_II.jpg' alt='Contax Serial Numbers' title='Contax Serial Numbers' />The Contarex lenses have become very popular with people using adapters to mount them on modern digital cameras. For the most part these new Contarex lens owners, being inexperienced in film cameras, have no idea of the risks entailed in putting a 5. Table 1. Lenses Tested. Most of the Arsenal and Hartblei lenses were based on optics formulated in the 1960s or 1970s, and are thus newer than the formulations. PM1010 FEDZorki 00302 from Alexey Nikitin Russia coll. PM1015. Further evolution of the particular camera with black vulcanite, instead of Contax leather already. Adams Idento, early version, 5x4, Ross 6in. Homocentric, Sands Hunter, London sellers label. With Adams film pack adapter. Rare the first one weve sold. Prevendo a demanda de ligaes em um call center por meio de um modelo de Regresso Mltipla. Forecasting a call center demand using a Multiple Regression model. There is a great danger of complete loss of the value of the lens in this. All Contarex lenses have a hidden built in self destruct that can happen suddenly and without apparent warning. This problem is the result of the lubricant used by Zeiss when the lens was assembled and also by the particular aluminum alloy used to make the focusing helical threads. This aluminum alloy is extremely highly susceptible to friction welding. Friction welding is metal welding that happens due to friction without heat. It will occur when clean aluminum bare metal is rubbed against itself. When the focusing threads of a Contarex lens become friction welded there is no possibility of repair. The focusing assembly is welded permanently and cannot be separated non destructively. There is no lubricant or treatment that can separate the moving parts that have been friction welded together. A friction welded focusing assembly in a Contarex lens is permanently ruined and there are no spare parts other than donor parts lenses and these have disappeared from the market. The lubricant used by Zeiss was supplied by a lubrication company in Germany that is still in business. I contacted them to inquire about obtaining a quantity of this lubricant. They replied to say that the lubricant is no longer available and was originally made of a product called shin oil. This is oil distilled out of the shin bones of cattle. The problem with this lubricant is that a lot of it was infected with a very slow growing mold at the Zeiss factory or when it was manufactured. The lubricant is composed of shin oil and thickeners. The mold slowly consumes the oil and does not consume the thickeners. The time frame for the action of the mold to completely consume all of the shin oil in the lubricant is ending right about now. Just how long it takes for the mold to consume the shin oil depends upon the storage conditions of the lens. Decameron Italiano Moderno Pdf File. A lens stored in warmer wetter conditions will have lubricant that deteriorates faster than one stored in cold and dry conditions. When all of the oil is eaten by the mold only the thickeners remain and they are not a lubricant and not only do they not prevent friction welding, they promote it. Friction welding can take place in about one to three turns of the focusing control. It happens so suddenly it surprises the lens owners. The most dangerous thing you can do is to try to loosen up a Contarex lens whose focusing action has become sluggish. This is the sure sign the mold is at or very close to the end of its work and that the lens is susceptible to friction welding. I recently purchased three 1. Contarex lenses whose action is sluggish. The next time their focusing controls will be moved is when they are disassembled and then only after their focusing threads have been lavishly drenched in special oil. This is a picture of the seized friction welded focusing helical of a Contarex 1. Sonnar lens. The large blackest part attaches to the focusing ring. You can see on the top the bright aluminum where the set screws scratched their attachment points when the owner used force to try to get the lens focusing control to move. You can see how the original black anodizing of the male threads has faded due to wear and the action of the acid produced by the mold as it consumed the lubricant. It took only two turns of the focusing control from 1 meter to infinity to permanently ruin this focusing helical set. You can pay 1. 60. Planar and then have it turned into a complete ruin in about 3. The same thing can happen to any other Contarex lens because they all used the same aluminum alloy and the same lubricant that is susceptible to mold growth. The original manufacturer of the Zeiss lubricant originally used in the Contarex has manufactured and supplied me with a large quantity of a modern synthetic lubricant that serves the same purpose but it is not susceptible to mold growth. The second problem with the particular aluminum alloy used in the Contarex lenses is that it needs a special lubricant to prevent premature wear and friction welding. The particular aluminum alloy chosen by Zeiss must have a specially prepared lubricant in order to prevent very rapid premature wear. Zeiss originally hard anodized the focusing threads, but this treatment does not last forty years as you can see in the photograph above. All of the Contarex lenses I have seen have had patches of threading where the hardened anodized portions have been worn through to bare metal and this bare metal is where the friction welding happens. All of the Contarex lenses that I have seen that have been serviced recently have been lubricated with ordinary vaseline grease the kind you can buy in a drug store. This will prevent friction welding but it will not prevent rapid premature wear. All of the lenses lubricated with vaseline grease have contained vaseline that is filled with bright shiny aluminum wear particles. Vaseline causes the surface of the aluminum to undergo a process called spalling, this is where tiny flakes of metal chip off of the surface in response to friction. The Contarex lens is a very special thing made of very special materials and it demands that only the proper lubricant be used in it. The Contarex Body When you buy a Contarex there are two things you cannot know and which cannot be known until the end of an overhaul. The first of these is you cannot know how long the camera has been stored fully wound. When a Contarex is fully wound all of the springs in the camera are fully tensioned. Springs will permanently loose their strength over time if they are kept fully tensioned. A Contarex that has been stored for 2. This always shows up in the 11. There are no replacement parts. The second unknowable thing is the state of wear to the shutter speed controller. The more it is worn the slower the final achievable 11. It is possible to clean, lubricate and then properly adjust the shutter speed controller but it is not possible to restore it from the state of wear that it is in. An overhaul will stop the wear and will protect it from future wear. The two factors of the loss of shutter curtain strength and shutter speed controller wear contribute, in my experience, to a possible after overhaul 11. Contarex cameras. The Contarex camera is very complex. It is extremely difficult and time consuming to adjust to extract from it the maximum performance potential when it is in an advanced state of wear, if the camera you buy happens to have been defective from the factory or if workers over the past 4. It is not possible for me to both remain in business and offer a performance guarantee on this camera line. In most cases my experience with this camera is the best that can be done is to completely disassemble the camera, thoroughly clean, assemble, lubricate and then adjust the camera so that it is as reliable and accurate as it can possibly be, and be protected against continued excessive wear due to dirty and unlubricated parts. There is no performance guarantee on any part of any Contarex camera I service.