Archived posting to the Leica Users Group, 1999/02/12
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Ted The idea is that the depth of field is quite a bit wider at same distance for a 35mm at f1.4 than for the 50mm at f1, thus leaving more room for 'acceptable error'. At same magnification whatever the focal length, f1.4 is more forgiving than f1 (and less than f2). Seems obvious to me. I have no figures right here, but they were published on this list, arguing on the precision of the M6 rangefinder and the acceptable tolerance between the exact point of focus and the point of focus indicated by the RF. Just as a 50mm at f1.4 is easier -or safer- to focus (precisely) than a 75mm at f1.4. So my idea, which is also supported in the LHSA article pointed to me by J. Beal ( http://wanda.pond.com/~lhsa/articles/summilux.html ), is that the most efficient 'master of darkness' in the M range might well be the 35mm f1.4-Summilux (asph) rather than the Noctilux, the 1 stop advantage of the Nocti being compensated by the probable better tolerance to slower shutter speed (1 stop ?) of a wider angle and by the security brought in by wider DoF.... Or am i missing something here ? Alan Ted Grant wrote: > > Alan Ball wrote: > > >And another question: isn't focusing MUCH more reliable for the 35mm at > >f1.4 than for the 50mm at f1 ?>>>>> > > Hi Alan, > > I really don't see why if the rangefinder is accurate, it's going to be > accurate for any attached lens, f 1.0 or 1.4. > > As long as those two little images come together correctly that's what > controlas the in focus and not the aperture. I think. > ted > > Ted Grant > This is Our Work. The Legacy of Sir William Osler. > http://www.islandnet.com/~tedgrant