Archived posting to the Leica Users Group, 1997/04/09
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]David, >> The other day I bought a 90/2.8 early black (sn, 22xxxxx). It looked very clean but focusing ring and its body were not black. It looked reddish black while the vulcanite portion on the bottom is black. I have seen black 90 before. They were all black. Has anyone seen this color?<< The reddish black color you are seeing is the result of the aluminum anodizing fading over time and exposure to sunlight. Early efforts at anodizing were not a true black, rarther it produced a purple/reddish black if the item was looked at in strong light. This was in part a result of the anodizing process applied to aluminum alloy of varying hardness/composition and the consistency of the anodizing process itself. As a result of the anodizing not taking as well to certain aluminum alloys as others, some parts were prone to fade/discoloration, which is what you are seeing on the 90/2.8. I have an early black 21/3.4 Super Angulon that suffers the same fading to a reddish purple color but only on the focus ring, the remaining anodized parts (lens body, etc.) are still quite black. It is a result of the process on the various alloys the lens components are made up of. Regards, Don