Archived posting to the Leica Users Group, 1999/06/15
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 04:59 PM 6/15/99 -0700, Austin wrote: >what does LTM stand for? > >And am I correct in guessing that 'M39' is 39mm as in the filter size of my >Elmar 50mm? No, it is not. The 39mm filter thread is 39mm by 0.5mm; the M39 (or 'Leica thread-mount', hence, LTM') is 39mm by 26 turns-per-inch, close enough to 1mm not to quibble unduly. M42 (or, and I cringe at the mere writing of it, "Pentax" screw mount) is 42mm by 1mm, while T-mount is 42mm by 0.75mm. And so forth. Marc msmall@roanoke.infi.net FAX: +540/343-7315 Cha robh bas fir gun ghras fir!