Archived posting to the Leica Users Group, 1998/09/12
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 11:38 AM 9/11/98 -0400, you wrote: >Eric, nothing slips past you!! But since I believe you know, does glass crack >when the temperature changes quickly from cold to warm or warm to cold, or >both?? This thought occured to me during this last heat wave when I was >cooling off my windscreen by pumping a/c out of the defrosting vents of my car >(truth be known, I didn't care much because its cracked anyway and needs >replacing). I was a chemistry major in college for a while, so these kinds of things come naturally. :-) I don't think you have to worry. The blast from canned air could be a problem with some low dispersion glasses, I'm told, but mostly big front elements. But with Leica lenses, I'd worry about any size. No need to blast on for 15-20 seconds without interruption (really, really really cold really fast), if they lenses are blasted once in a while, so the big crud doesn't accumulate. - -- Eric Welch St. Joseph, MO http://www.ponyexpress.net/~ewelch Profanity sucks.