Archived posting to the Leica Users Group, 2003/07/31
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Thanks Eric. That clears the air nicely. You're nearly correct. :) But "fast" (aperture) has nothing to do with it. Your eye sees the same "fine adjustment" in the rangefinder regardless of the aperture (or focal length) of the lens. The difference with an SLR ( as you note) is that the long lens magnifies the image in the viewfinder, and thereby allows us to see differences between much finer adjustments. For techies: the viewfinder magnification in the SLR increases the effective baseline making it easier to focus long lenses. Can we stop now? I promise to keep quiet as my contribution. Mike Quinn .Eric Welch wrote: > Doh! It just came back to me now why a rangefinder is more accurate > with wider lenses! > > I was right, but for the wrong reason. I've been arguing an old reason > that an expert once told me was incorrect. I just forgot about that > part. > > The REAL reason rangefinders are less accurate is that your eye Is less > able to distinguish fine adjustment to focus with fast longer lenses. > It's not the camera, it's US! > > You're right, the rangefinder's accuracy doesn't change. Just our > ability to distinguish accurate focus. The level of accuracy is more > "adequate" with wider lenses. It's advantage becomes less with longer > lenses. But it's our fault! The way the real world works, the effect is > that we can focus better with a 35mm 1.4 lens. - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html