Rangefinder close focus calibration

[gliderbee]

I'm trying to calibrate my Hexar RF Rangefinder; as per instructions I found on the internet and on this forum, I calibrate with focus on infinity, but then, the close-focus calibration is by 2cm off; I'm using a Hexanon 90mm F2.8.

Questions:

- should I do the calibration with another lens, e.g. 50 or 35, or doesn't it matter ?

- how can I get both infinity and close-focus calibrated ? Is there another screw I should turn ?

Edit: by calibration, I mean "alignment"

Thanks,

Stefan.

 

[Steve M.]

Try setting your close focus first. Being off a small amount at infinity isn't going to make any difference at all, especially as you'll probably be stopped down then.

 

[awilder]

With the top cover of the camera removed, there is a slotted close focus calibration screw hidden under a small black paper (?) cover near the lower left hand corner of the viewfinder window. The cover is easily removed with a pair tweezers as it's only held in place with a little glue. Turning the screw a few degrees will change the focus rate of the rangefinder mechanism to allow you to match it to the lens. Of course you'll also need to re-adjust the infinity setting of the camera when doing this. I've done it but requires a bit patience because it takes a few attempts to get it right for both far and close. My advice is to have a Konica repair expert like Greg Weber do it for you.

 

[gliderbee]

@steve: I thought about that, and I will do it that way if I can't get the other idea to work; it would be nice though is everything worked as it should (wouldn't it be always 😛 ?)

@awilder

I have looked for that small screw, but I don't find it (although the place isn't THAT big 🙄). Would you mind indicating it on this picture ?

Thanks,
Stefan.

 

[awilder]

The near focus adjustment screw under the small rectangular black cover is located on the front side of the camera, not the back as you've pictured. Looking down from the top, it's between the viewfinder window and the frameline illuminating window. Unlike the infinity adjustment screw, this one is a little bigger and easier to turn.

 

[Arjay]

Awilder was faster ... 🙂

I think awilder meant that you ought to look at your camera not from the viewfinder eyepiece side, but from the lens bayonet side. Then, his description ought to make sense.

 

[gliderbee]

Yes, I indeed misunderstood first.

I've found the paper, which was already loose, so I guess the previous owner has been there; there are TWO screws ... (first nothing, then two ..). Which one should I turn: upper or lower ? I replaced the picture for reference.

BTW, what's the best choice: testing with a wide lens or a tele ?

Thanks a lot for your help. What would I do without the internet and this forum 🙂

Stefan.

 

[awilder]

Hi Stefan, here's a link to the rf adjustment post with pictures, drawings and narrative: http://www.rangefinderforum.com/forums/showthread.php?t=1937&page=2

The screw is located under the hole on the far left side of you picture, apparently the black cover has been removed. The two brass screw on the right side of your picture are not it. I was wrong about the near adjustment screw location, it's to the left of the frameline sub-assembly. It's been awhile since I looked at one of these. The link I gave you has a schematic from Issy on 2/16/2007 and the adjustment screw is called the "Roller Adjusting pin". Test with either the 50/2 Hexanon or the 90/2.8 Hexanon. Without even focusing the camera through the finder, you should first bracket focus shots based on the lens' distance scale index to determine if the focus setting is accurate for the camera, i.e., set the camera at exactly 1 meter from a target to the camera's film plane index and take a shot with the lens set at 1 meter. Then, without moving the camera, take a few shots with the lens set at small +/- settings around the 1 meter mark to see which is sharpest on film. Use the sharpest setting as you reference for 1 meter callibration of the rangefinder.

 

[awilder]

For me infinity is a distant tower 1/4-1/2 mile away on the Hexar RF. Beyond that the diference is nil.

 

[gliderbee]

Ok, before all this is becoming too philosophical :angel:, IT IS DONE ! Thanks for explaining all this; my Hexar now focuses apparently correctly at 1m and .. well ... beyond 5 meters, since infinity distance does not exist. I'll give it a try with a short piece of testfilm, but it looks good.

Stefan.

 

[Sparrow]

Star Trek ...