Archived posting to the Leica Users Group, 2008/04/20
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]On Apr 20, 2008, at 6:46 AM, Leonard Taupier wrote: > This is a very interesting issue. I don't know if anybody has > mentioned what happens to the depth of field of the Noctilux, or any > other lens, in a Leica film camera versus the M8 digital camera. It > seems that nobody complains about the focus on a film body but all > kinds of complaints on the M8, especially the Noctilux, Summilux > Asph and the 75mm Summilux. Is there a difference? Yup, there sure > is. I tested 16 leica lenses for depth of field at a distance of 8 > feet. I tested 13 of the lenses with film using a .85 MP and > compared the results to those taken with an M8 and a 1.25 Leica > magnifier. > > In every case the DOF shifts away from the camera with the M8. In > other words the lens appears to back focus. The worse lens for this > shift is the Noctilux. But even on a film camera it is barely in > focus. The typical back focus shift of any 50mm Leica lens is about > 4 to 5 inches at 8 feet with the M8. The backward shift of the > Noctilux is between 8 and 9 inches. This puts the focused point of > the rangefinder outside the depth of field of the lens. The other > thing I noticed is the DOF is better centered on the older LTM > lenses then on the newer lenses. I don't know if this is a quality > control problem now or if the focus point test has changed. I tested > 7 LTM lenses, the Xenon, Summarit, Summitar, Summicron Coll, 50 > Elmar RS, 90 Elmar and 135 Hektor. The focus point nicely stayed > within the DOF on both cameras. Of the M lenses the best is the 1st > 50mm Summicron rigid version followed by the current 50mm Summicron. > > I verified my results with a second M8. The MP body is one year old > and purchased new. I also sent my Noctilux and 75mm Summilux to DAG > for focus adjustment even though the lens is still in warranty. I'm > also shooting more with film these days. hi Len, is it appropriate to send a Noctilux to DAG for focus adjustment, without the body... does that work out OK? I agree that with film (bodies) I did fine with the Noctilux wide open, with the M8 much less so... Steve > > > Len > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information best, Steve "I never wanted to be famous" http://www.blurb.com/bookstore/detail/186890