Archived posting to the Leica Users Group, 1997/11/16
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]>>Still: Why SL mirror lock for the retro 4/21 R SA? > >I think the lens in question is not retro focus. I have seen one of >these once and it has a rear element that protudes into the camera body >right where the mirror is. This wasn't unusual with extreme wide angles in the early days of SLRs. A number of camera brands (including the Leicaflex and the Zeiss Contarex) had a 21mm non-retrofocus lens which required the mirror to be locked up, and used scale focusing and a separate viewfinder. It took a while for many companies to get up to speed with retrofocus designs. This is also the reason that some companies had 55mm, 58mm, etc. normal lenses in the 1950s and 1960s; they made them just long enough so that they did not have to be retrofocus. - - Paul