Archived posting to the Leica Users Group, 1998/10/27
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 03:23 PM 1998-10-27 -0500, B D Colen wrote: > >135 has always struck me as a somewhat weird focal length - not long enough >to be a useful telephoto, but - for me anyway - a bit too long to be a good >portrait, close distance lens. I suspect the only reason the focal length >really exists is that it was the longest focal length that could >realistically - sort of - be used with the rangefinder (Leica/Contax) and as >a focal length it was initially picked up for the reflexes. Well, that is why it was retained - but it first was selected as a focal length as 135mm was the shortests focal length at which the original Tessar formula could provide full LF plate coverage. So there were a lot of 135mm lenses around for LF work, and these were simply adapted for miniature-format use, first on the Leica and, almost immediately, with the Contax 4/13.5cm Sonnar, a lens Kuc contends was first contemplated for 9cm by 12cm use. Zeiss, of course, found focusing accuracy was achievable with the 6.3/18cm Tele-Tessar but had difficulties with the RF-coupled Olympia Sonnar, so this was replaced with the highly valued 2.8/18cm in the Flektoskop reflex housing. Hence, by 1937, both Zeiss Ikon and Leitz had restricted themselves to a long lens of 13.5cm, a focal length worthy of our high regard for its longevity -- and usefulness! Marc msmall@roanoke.infi.net FAX: +540/343-7315 Cha robh bas fir gun ghras fir!