I'm considering buying the Leica 135mm F/4.5 Hector or the Leica 135mm f/4 Elmar - both post war. The Hector dates to 1952 and the Elmar is a 1961 vintage. What I would like to know is how do the two lenses compare wide open, at f/5.6, and at f/8. At F/11 & beyond I think that they would be about the same. What size filters do the lenses use? I do not want a Tele-Elmar or Tele-Elmarit, this is for a crazy project of mine that needs a long focus lens. If you have used either lens I'd like your thoughts on them. BTW, I have a black Canon135 f/3.5 LTM but do not want to use it. Thanks!