Often these coatings will be discoloured by oils and moisture leaving small bright spots or patches. I cleaned gently with isopropanol followed by methanol with no problems. Not only do they easily scratch and rub off but cryolite is soluble in warm water. (Note that extreme care must be taken when cleaning these old anti-reflective coatings. The exterior of objective lenses shows no traces of coating (if it ever was coated) and the ocular assembly was not disassembled so it is not known if the interior ocular lenses are coated but I am guessing they are. Interior of objective lenses, prism faces and outside of field lens are reportedly cryolite (sodium aluminum fluoride) anti-reflective coated which transmits light better than the usual magnesium fluoride but is more fragile. Perhaps I am fortunate to have a particularly good example or more likely I need to look through a Zeiss 7X50 HT or 8X60 to fully understand. I am also surprised that the consensus of opinion among knowledgeable and experienced collectors is that optical performance of this binocular although good is not exceptionally good. I am surprised that it can deliver this performance in spite of having some chipped prisms (its anti-reflective coatings, though, are still in very good condition). Optically this is now the best 7X WW II military binocular in collection: superior in every way to the Ross Binoprisms and Barr & Stroud CF 41 especially in sharpness toward edge of field noticeably brighter and sharper than the excellent Barr & Stroud CF 25 and somewhat brighter than even the coated B&L Mk 28 and REL’s. This is certainly due to the interest of the many German WW II militaria collectors and as well as to Germany’s well deserved historical pre-eminence in the manufacture of high quality and innovative optical instruments. The market value of WW II German hand-held military binoculars is very high compared to those of other countries and excepting the very finest ones (most made by Zeiss and of 7X or greater magnification) does not always reflect optical quality or rarity. The type iii) is the most common variant but in good condition with rubber armour intact may have same or greater value than the other types. Although often called “U-boat binoculars”, these were also much used on surface vessels. This type has coated optics, desiccant cartridge housings and is rubber armoured (often missing in part or whole and/or in dilapidated condition) with different style ocular housings than previous models.
#Leitz wetzlar germany elmaron serial
iii) “beh” Marked with Rubber Armour, Serial # Range at least 440763 – 474439. Seeger shows such a binocular (serial # 431687) on page 291 which is identical to this collection’s example pictured above. Later examples beginning with at least serial # 431583 do not have these two markings but still have coated optics and additionally have housings for silica gel desiccant cartridges on the prism plates with each prism plate secured to the chassis by a large ring instead of screws. Earlier examples of this type are marked “T” indicating coated optics with a Kriegsmarine eagle. ii) “beh” Marked without Rubber Armour, Serial # Range at least 328770 -436830. This type also has a Kriegsmarine eagle marking and usually does not have coated optics. Leitz Wetzlar” Marked-Serial # Range at least 238203 – 310223. Notes: World War II Leitz Porro II 7X50 binoculars (called "tuna cans" by the Germans) are serial numbered at least 238203 – 474439 (however, this is not sequential because other model Leitz binoculars have been seen also manufactured and serial numbered within this range) and, as suggested by Rohan, can generally be divided into three types. Manufacturer/Model: Leitz beh Kriegsmarine (type ii) 7X50įield of View: 7.3 deg = 128 m/1,000 m APFOV 51 deg
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