Archived posting to the Leica Users Group, 2005/04/14
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]On Apr 14, 2005, at 10:47 AM, William G. Lamb, III wrote: >> Why aren't the framelines in the M's (I have a TTL) very >> accurate for framing? Is there some special technical challenge >> involved? >> >> Scott The M finder only compensates for parallax shift in x and y, but does not compensate for a shift in focal length by zooming in / out in z. The focal length of a lens changes very slightly as you focus from close-up to infinity. A 50 may be a 50 at 1 meter, but when focused at infinity it may shift slightly and become a 48 or something. Anyone with more optical expertise, please chime in and correct me if I am wrong. Starting with the M6, Leica shrank the frame lines. There are several theories why they did this: a) Sometime during the 1980's Leica 50's gained the ability to focus as close as 70 cm. Previously they were mostly limited to 1 meter. The new frame lines reflect that change. But how often do you shoot at 70 cm? I bet most shooting is done from 3-5 meters to infinity. b) Leica crammed more framelines in to the finder and needed to shrink everything a little to fit. Old cameras have markings for 35/50/90/135. New cameras show 28/35/50/75/90/135. c) They needed extra room for the meter read out, but I find this explanation difficult to believe. The meter dots are pretty far down. Regardless of the reason, these changes mostly affected the 50mm and 90mm markings. I think they are about 10-15% smaller than the old ones. The M2/M3/ M4/M5/M4-2 and some M4-P all have the old style, bigger frame lines. This is my pet peeve about the current Leicas. I rarely shoot a 50 on the newer bodies, unless I really need the built in meter. I do not expect absolute accuracy from a rangefinder, that is the domain of the SLR. But to me the 50 markings on the newer cameras are so far off, as to be unacceptable, even for an RF So, I mostly shoot the 35 on the new bodies and keep the 50/90 on the older ones. One solution is to use a VIOOH finder, which is surprisingly accurate, especially at infinity. Feli ________________________________________________________ feli2@earthlink.net 2 + 2 = 4 www.elanphotos.com