Oh great esteemed colleagues:

My M6 rangefinder is out of whack. Post focus. How often do others need to get the rangefinders adjusted? Mine was done after purchase 3 years ago and has traveled moderately. Does the high frequency vibration of the turbine engines tend to cause them to shift faster. The camera has not been abused or dropped (IMHO). Thank-you for your patience and correspondence.

-- Mark A. Johnson (logical1@catholic.org), May 26, 2002

Answers

I sell surveying equipment; buyers ask "how long will the level stay calibrated?.......It all depends on the shock and vibration history that the unit sees..Also an abrupt temperature may cause the alignment to move off.............I have bought a 30 year old Zeiss Ni2 auto level off of ebay that the lenses were all fogged up; and the case had one cupfull of dirt in it; but the level was almost perfectly aligned......

When we buy a new batch of levels to sell; they arrive by UPS ; we check and align them all before selling them...Home Depot and Lowes never check them....the ratio of ones we have to align to total received varies randomly.. it maybe 1 in 6 ; 5 of 6; 0 in 6; 2 in 6 for the same model level.....This ratio varies with the coffee and donnut factor; the workload of the UPS guys; and moon phase.........

At Burroughs in engineering we would place a spring wound shock & vibe recorder to record the 3 axis inputs to our valuable equipment shipped..it would be hidden in the crate to record one weeks of shock and drop! data...

My Bessa R went out of alignment when it took short tumble; it was in case too....Kelly

-- Kelly Flanigan (zorki3c@netscape.net), May 26, 2002.

I doubt very much the rangefinder needs calibration, it just needs zeroing.

Set the lens to infinity and point the camera at something AT LEAST THREE KILOMETRES AWAY; preferably farther if you can (there is a fullish moon tonight). If the split images do not line up horizontally then turn the screw attaching the roller to the rangefinder arm slightly. Check it again and, now you know which way the adjustment is moving the image, tweak it again. Only move it a little bit at a time.

Use a screwdriver that fits! You do not want it to slip.

Only turn the screw, DO NOT PUSH AGAINST THE RANGEFINDER ARM.

A very simple adjustment that every Leiva M user should know how to do.

-- John Collier (jbcollier@shaw.ca), May 26, 2002.

This method of zeroing is interesting. I always thought that one had to adjust the screw under the red dot.

I have some instructions from the web for aligning the rangefinders on screw mount Leicas. These instructions offer a method similar to the under the red dot method, I believe for horizontal alignment - In the case of LTM cameras, remove the screw cover on the front of the camera near the rangefinder, then reach inside with a small screwdriver and turn an adjustment screw.

My IIIc rangefinder is off consistantly throughout its range - Infinity on the lens corresponds to the two images coincident at a closer distance, and so on throughout the focusing range.

How should I zero my rangefinder on the IIIc - with the screw near the rangefinder window or by adjusting the screw on the roller?

-- Tom (therbert@umiami.ir.miami.edu), May 26, 2002.

The roller cam sets the infinity adjustment horizontally..on the Leica .This is used for focusing..The hidden screw sets the vertical adjustment..My camera has never required me to adjust this screw... the close up horizontal adjustment is set by the eccentric on the pivot arm of the roller cam..it adjusts the arm length; which sets the gain of the focusing rangefinder system....Have a pro do this unless you are mechnically inclined...On Russian LTM cameras; such as the Zorki and the FED; the horizontal adjustment for infinity is where the vertical adjustment is on the Leica....This causes some confusion because their is sometimes missinformation on the web....The Leica M3 repair manual is available on ebay as a PDF file on a CD..It discribes the alignment also..Kelly

-- Kelly Flanigan (zorki3c@netscape.net), May 26, 2002.

The thread mount Leicas also have the infinity adjustment behind the dummy screw between the windows--vertical alignment is by turning the RF window nearest the shutter release.

-- Michael Darnton (mdarnton@hotmail.com), May 26, 2002.

It appears the body is correct in the near range (1-2 meters) and off at infinity. I will see about sending it out, possibly DAG.

Thanks for the feedback.

-- Mark A. Johnson (logical1@catholic.org), May 26, 2002.

Then the length of the rangefinder arm needs to be adjusted. It can be done at home but it is easier to have a professional with the right tools do the job. DAG is a good M repair place.

-- John Collier (jbcollier@shaw.ca), May 26, 2002.

UPDATES:

The body checks out fine. I shot a series of frames using different lenses. I used a 90 Elmar, 90 Tele-elmarit, 90 Summicron and 135 Elmarit shooting a tape measure a 40 inches and also at 120 inches. The 90 Summicron failed at both distances, all of the others were within 1/4" at 40" when shooting wide open. Thanks for the support and information.

M.J.

-- Mark A. Johnson (logical1@catholic.org), May 30, 2002.