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The block diagram for your lens appears to be a variation of the Zeiss Tessar design created by Dr. Ralph Rudolph. Roger Cicala, in one of his excellent blog entries at lensrentals.com says: Literally dozens of today’s excellent lenses are simply modifications of the Tessar: Leitz Elmars, Zeiss Sonnars, Kodak Ektars, Schneider Xenars, Voigltander ...


1

The only way to get your lens to focus to infinity, is to move the lens further from the film/sensor plane, to where it was designed to be. I assume it can be made to focus if i change distance between lens elements? What elements i need to space out to restore focus ability, can correct spacing be figured out mathematically? What is the basis of your ...


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Lens designs, even in the olden days, are highly optimized for sharpness and several kinds of optical aberrations. Even small changes, including distance between elements, are bound to degrade image quality. So, usually, you don't want to tamper with the existing design. Instead you add lenses, either in front (fish eye lens) or between lens and camera (...


5

This is exactly what a telecompressor/focal reducer/"speed booster" is for. It can be bought as a ready made unit with a choice of mirrorless camera mounts on one side and a choice of SLR/DSLR mounts on the other. Since these devices are more expensive than normal adapters, it can be worth buying strategically in case you have multiple legacy ...


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There's no way to remove something that isn't there. The fungus has etched away part of the coating or even the glass itself. It's gone.


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The most common causes of internal haze in lenses can be divided into three main areas: Surface contaminants. Oil, grease, heavy dust, or even a thumbprint left by a careless technician. Fungus. This can usually be identified by the 'spiderweb' patterns. Balsam Separation. Pine balsam was once the primary material used to bond multiple lens elements ...


2

On internal elements: Vaporized and condensed lubricants from aperture mechanisms, leaf shutters and other lens mechanics. Sometimes, other liquids that got inside and got trapped/washed stuff onto glass surfaces/left a residue (eg fleamarket lenses that got wet or suffered condensing moisture). On external surfaces: Urban air pollution, tobacco or other ...


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