Archived posting to the Leica Users Group, 1997/09/09
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]>To: >INTERNET:Leica-users@mejac.palo-alto.ca.us > > If a lens fogging problem with 90mm T-E's "was discussed some >time ago on LUG", then I missed it. As I remember it this discussion centered on the use of sperm whale oil as a lubricant in the lenses. This provided smooth focussing, but it was prone to volatilizing if the lens was kept hot (used in the tropics, left in a car in the summer, etc.). This oil vapor would then coat itself on the internal surfaces. The oil coating can be cleaned off, and a synthetic lubricant can be applied to prevent the problem from occuring again. In the end the problem was more of an issue for those buying used lenses. People thought that it was something to be aware of, but it's not as grave a difficulty as having fungus grow on a lens. If you own a 90 T-E that you like then the need for concern is minimal. If you ever do get the fogging then you can have it cleaned and your lens will be as good as new. I wouldn't fret. Life's too short to worry about such remote possibilities. - -Charlie