Archived posting to the Leica Users Group, 2003/09/13

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Subject: [Leica] Impact and lens mount of R8, Focus shift?
From: Martin Krieger <krieger@usc.edu>
Date: Sat, 13 Sep 2003 23:32:53 -0700
References: <200309131622.JAA19363@mejac.palo-alto.ca.us>

About two months ago I tripped and fell head first, my R8 (with a Schneider
Super Angulon PC 28mm lens) in my hand. The camera went down lens first,
still in my hand, the lens hood now well bent out ofshape. The metal lens
hood protected the lens itself, but the focus was stuck and the lens is now
being repaired somewhere in Leicaland. The body seemed fine, and the slides
I shot later that day were as good as the ones shot before the fall (the
lens had stuck in a suitably close to infinity position, so that I could
continue shooting "in focus").

I recently decided to be sure, and shot some test shots using the 35-70 3.5
lens (at both 70 and 35mm), and Kodachrome 200. It would seem that the best
focus for very distant points, discovered in the split image finder, was not
infinity. In fact, the infinity setting gave less definition than did the
split image finder setting, which was shorter than infinity (but these were
quite distant buildings). I examined the slides with a 22x loupe, looking
for patterns of mullions on a high rise.

I am now thinking that perhaps the lens mount was a bit pushed in due to the
impact (not at all apparent from visual examination of the body). Normally I
shoot with the 28mm PC or the 19mm 2.8 Elmarit lens. And I use the grid
screen, normally, so I do not have split image. So the focus for distant
points is not readily differentiated on the screen, and depth of field
charts would so indicate. (Tests of the lens mount with the 19mm were
inconclusive, and hence the use of the longer focal length lens that I
happen to have.) But under a 22x magnifier on the slides, one can see
differences. They are much harder to see with a 8x magnifier.

Does it make sense to think the lens mount is in trouble. Or am I asking too
much? Or is it that one should just ignore the marked distances, and rely on
one's eye and the screen (maybe with a magnifier in the eyepiece?).

Yes, these are handheld images. So none of this would pass muster as
"serious" testing. And I used K200 in part to have a higher shutter speed
and in part because it was the film in the camera and I had some shots to
finish off.

Martin

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Replies: Reply from "David W. Almy" <dalmy@comcast.net> (Re: [Leica] Impact and lens mount of R8, Focus shift?)
Reply from "Gerry Walden" <gwpics@aol.com> (Re: [Leica] Impact and lens mount of R8, Focus shift?)