Fast 50 on a CL

[wlewisiii]

Be sure to let us know how it works for you. Up close & wide open probably won't be easy - but you'll be in a good place to tell us 🙂

William

 

[Matthew Runkel]

Maybe I'm a little confused about the focusing issue. But can't you just close the lens to f8 or something, focus, and then open it back up before you shoot?

Or is it because the depth of field is so shallow at 1.4 that the inaccurate short base length makes it difficult?

Sorry if this is a noobie question, but I am, well, a noobie.

The second idea is correct. You can miss the focus point even though, as best you can tell from the rangefinder, the focus is right on. In other words, the rangefinder isn't accurate enough. The first idea cannot be right because there is no linkage between the diaphragm and the rangefinder.

According to Erwin Puts, the CL has an effective base length of 18.9mm, compared to 49.86mm for the .72 Ms, 63.71mm for the M3 and 9.82mm for a Leica SLR with 50mm lens. Puts suggests that you need at least an effective base length of 17.9mm to focus a 50/1.4 accurately wide open, allowing for a .03mm circle of confusion, but he is not taking account of subject distance. His figures suggest you are still better off with a properly-calibrated CL and 50/1.4 than with an SLR and 50/1.4.