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M8 rangefinder DIY and other myths?


dante

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Dante,

 

first of all, nice post. But! I have the feeling that you are arguing a point which no one is disputing. I have personally been advocating learning self-tuning for the rangefinder system, and have myself tuned all the tuning points I could reach, ie. the wheel, the pivot, and the vertical adjustment behind the Leica dot.

 

However, I only advocate doing this if your particular set of lenses is consistent. Typically, the lenses are well tuned and the camera is not, and this is where self-tuning can help. In the case that one or more lenses are off, no amount of rangefinder tuning will fix it. I had to send away my 50 Lux Asph twice, to get it right. The rest of my lenses are all on.

 

The best way to see if problems are caused by the camera is to take your most critical lens, typically a 90 Cron, 75 Lux, 75 Cron, or 50 Lux, and tune it with the wheel so that it is perfect at infinity (a star in he night sky is perfect). If it then also focuses perfectly up close, then all is well, and you can then check that all your other lenses work too, which they mostly will.

 

However, if it is off there, it depends on how the rest of the lenses are doing what you do next. If the lenses all have the same symptoms, ie. perfect far but off close, then you could consider if you want to try adjusting the pivot, which balances the near-far ratio of the mechanism. If you don't feel comfortable with this, you should send it away.

 

The last adjustment, the vertical offset, is likely to be set properly most of the time. Mine wasn't. Removing the Leica dot was easy, but took a lot of time. Adjusting the vertical was easy, but nerve-wrecking. Again, a distant star and a critical lens will help you get it right.

 

But all of this works only for lenses which work right. If one or more lenses are off, they need to be sent away.

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Personal opinion is that Dante and Carsten are saying the same thing (now watch how I try to make this obviously false point):

 

1) There's a lot more to the rangefinder than just "remove the lens and adjust the tracker roller."

 

2) If you are absolutely sure that you have the tools and knowledge to do the adjustments, do it.

 

3) Most people have neither tools, knowledge nor patience enough to make the adjustment, so general advice is: Don't attempt it; send it to Leica, or at least to someone more experienced than you.

 

 

BTW, I believe that Leica NJ also does M8 rfdr repairs instead of returning them to Solms. Please correct me if I'm wrong.

 

--HC

 

@ Dante--your thread tags are well conceived. Only one additional comes to mind, the computer help desk term pronounced "I D ten T" and written "ID10T." ;)

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Personal opinion is that Dante and Carsten are saying the same thing (now watch how I try to make this obviously false point):

 

1) There's a lot more to the rangefinder than just "remove the lens and adjust the tracker roller."

 

2) If you are absolutely sure that you have the tools and knowledge to do the adjustments, do it.

 

3) Most people have neither tools, knowledge nor patience enough to make the adjustment, so general advice is: Don't attempt it; send it to Leica, or at least to someone more experienced than you.

 

 

BTW, I believe that Leica NJ also does M8 rfdr repairs instead of returning them to Solms. Please correct me if I'm wrong.

 

--HC

 

@ Dante--your thread tags are well conceived. Only one additional comes to mind, the computer help desk term pronounced "I D ten T" and written "ID10T." ;)

 

Let me add one more number to the process:

 

4) If you're sooooo peeved by an obvious backfocus problem that you're going to send the camera (and lenses?) to Leica or Kindermann or somewhere else for calibration, and have three hours to spare and aren't slap-happy, then try the infinity adjustment as described on this forum.

 

You have nothing to lose if you're sending in the camera anyway.

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I can think of 4 and see 3 inside the lens mount. Verticle alignment (Behind the red dot), Near focus point, Infinity focus point and the close focus stop. The last 3 are what can be seen inside the mount.

 

The other two are the magnification of the rangefinder patch and the screw which adjusts how the frames move for parallax correction. There are then other adjustments for the frame selection based on the position of the frame selection lever.

 

The adjustment of the 3 inside the lens throat is a lot easier if you remove the plastic base plate - 5 screws, Philips 000 screwdriver - and there is a rubber plug at the base of the lens throat. Push that out from underneath and you can insert long flat blade/hex screwdrivers up though the base of the camera to adjust all three.

 

Vertical alignment does indeed need removal of the red dot - I think Carsten worked it off with tooth picks but you do risk marring the finish and/or destroying the red dot. Alternatively, just two screws once the base is off and the top will come off giving you full access to everything.

 

I agree about using quality tools matching the camera you are working on. I use tools from Facom: Part No 84E.J1 - a set of 5 hex drivers, including a long 2mm which is long enough to reach from the bottom of the camera. (Bienvenue sur le site de FACOM)

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  • 2 weeks later...

Mark, I have been trying to find the set you are talking about, but the site search does not seem to work. I presume it is in the General Tooling>Screwdrivers, keys and bits>Keys section, somewhere. Are they T-handled, or in a sleeve or wallet? Did they change their name? Thanks for any tips.

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Today I was shooting with a friend (new M8 owner). He was using my 90/2 APO lens and all the pictures were slighty out of focus. I don't have that problem with my body.

 

This afternoon, we tried to focus a building (more than 5Km distance) and with his camera the building was in focus just a tiny bit before the infinite stop of the lens.

 

Tonight, we tried to focus the moon and it was just the same thing. We get the moon in focus just before we reach the infinity stop on the lense (0.5~1mm)

 

We've done after that also a test at home: to focus the LCD TV speakers (very small square holes) at a exact distance of 2 meters. We just get them in focus a bit before 2 meters indication on the lens. On the RF it looks like the image splitting goes a bit to the right side.

 

We used the Leica 1.25x magnifier and Megaperls 1.15x and 1.35x to be more accurate (and combinations of these three magnifiers).

 

He would like to test correct this "at home" (very fustrating to send the camera to Solms after 3 days of use)

 

So my question is: Should we turn the 2 mm allen key (I have one at home) counter clock wise or clock wise?

 

Thank you for your advice.

 

Cheers!

.

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It is not that serious. Just turn it one way, and notice if it is better or worse... You have to be ready anyway, in case you go too far.

 

Thanks Carsten.

 

I suppose I only need to move the wheel screw very little. We'll try to do that tomorrow. He's comming for lunch.

 

Cheers!

.

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Schedule at least 30 minutes, and maybe you'll spend less time on it.

 

Great fun to do it... but it took us almost 3 hours and more than 200 pictures!

 

Bloody hell, the wheel mechanism is really sensible!!! You turn less than 1mm and all changes. We have tested "infinity", 25m, 10m, 2m and 1m. Just for a fraction of mm when seems OK "infinty" you see it's not OK at 1m and viceversa. It's very difficult to obtain the right point (even with a very high quality allen wrench), especially CCW because the wheel moves towards the shutter.

 

Besides using magnifiers and diopter corrections change values slightly.

 

After two and an half hours we got an amazing result. We couldn't go further to a certain point but the limitation is our eyes and the mechanical accuracy.

 

The most important thing is that my friend Jean Bernard is very happy with the results.

 

Cheers!

.

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VERY VERY small adjustments Warning. it's a touch sometimes

 

INDEED! In another thread Pascal Meheut said to move 1/10th and I assumed 1/10th of 360°... so I moved it about 35° CCW... I let you imagine the result...

 

What I found out is when the issue is back focus, you should move the screw counter clock wise.

 

As I said, the most difficult thing is just to apply the right force to the allen wrench to move it very little (and your eyes to focus in the most accurate manner). Maginfiers and diopters are tricky!

.

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Guest guy_mancuso

I also found it easier to turn the camera upside down on like a rubber mat or something so you can hold it steady as you make the adjustments , seems to help a lot

 

Yes and making a big adjustment may take hours to get it back to being even close. We never did say how small that adjustment really is. Our bad

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