Jupiter 3

T

tardegard

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I am sorry, I know there are several threads about it, but I just can't get it done.
I have this jupiter 3 lens just arrived, mounted on my Leica m240 and it back focuses. I tried another adapter, same story. I am trying to follow these instructions here http://ussrphoto.com/Wiki/default.a...entID=1570&Item=Jupiter-3+Clean,+Lube,+Adjust , but the are truly difficult to me. I don't understand much. Can you guys, anyone try to help understand how to shim this lens in order to correctly focus? I focuses fine via live view thoough. It's the RF that doesn't work.
 
tardegard said:
I am sorry, I know there are several threads about it, but I just can't get it done.
I have this jupiter 3 lens just arrived, mounted on my Leica m240 and it back focuses. I tried another adapter, same story. I am trying to follow these instructions here http://ussrphoto.com/Wiki/default.a...entID=1570&Item=Jupiter-3+Clean,+Lube,+Adjust , but the are truly difficult to me. I don't understand much. Can you guys, anyone try to help understand how to shim this lens in order to correctly focus? I focuses fine via live view thoough. It's the RF that doesn't work.
Click to expand...

RFF member Sonnar Brian would be the expert to help you out on your J-3, give him a PM.
 
J-3 is more complicated for shimming than other FSU RF lenses.
The shimming is still the same, unscrew lens block from focus block.
https://youtu.be/6p_1io9VtUE?t=96
Use original shim as template to cut new shims. I use paper.
Put it back with new shims. Check with digital M via RF. Adjust shims accordingly.
Once you are good at 1 meter mark it should be fine for the rest due to DOF.
But aperture ring is going to be shifted with new shims. You need to tap new holes.
 
Ko.Fe. said:
J-3 is more complicated for shimming than other FSU RF lenses.
The shimming is still the same, unscrew lens block from focus block.
https://youtu.be/6p_1io9VtUE?t=96
Use original shim as template to cut new shims. I use paper.
Put it back with new shims. Check with digital M via RF. Adjust shims accordingly.
Once you are good at 1 meter mark it should be fine for the rest due to DOF.
But aperture ring is going to be shifted with new shims. You need to tap new holes.
Click to expand...

Yes, i did it, i used some metal shim I found here. It seems to focus right now.
But i lost infinite focus. It doesn’t focus past 50 meters or so.
 
tardegard said:
Yes, i did it, i used some metal shim I found here. It seems to focus right now.
But i lost infinite focus. It doesn’t focus past 50 meters or so.
Click to expand...

Strange. I shimmed mine and it is fine on infinity even @f1.5.
 
Sonnar Brian said:
Please setup a ruler or tape measure, take a picture at 1m distance using the rangefinder. Then find the point of actual focus. That will give a good idea of the change required to the shim.

https://www.rangefinderforum.com/forums/showthread.php?t=173038

I wrote the instructions posted on the ussrphoto website. They cover most cases.
Click to expand...

Yes Brian, thanks, i tried to follow some but i have no experience in disassembling lenses. The problem here is that after I shimmed my j3 (black copy) I lost infinite focus. It doesn’t go pas 50 meters or so no. Is it normal?
 
tardegard said:
Yes Brian, thanks, i tried to follow some but i have no experience in disassembling lenses. The problem here is that after I shimmed my j3 (black copy) I lost infinite focus. It doesn’t go pas 50 meters or so no. Is it normal?
Click to expand...

At F1.5 do you have good focus at 50meters? Or stopped down to F4 or so, out to 50m?

Being out of focus used wide-open at 50m is normal. The lens has a longer focal length than the Leica standard 51.6mm. You can do 1 of 2 things: make the focal length shorter by grinding down the barrel to move the rear group in closer to the front. That takes a lot of work.

OR: this is where the "infamous" Sonnar/ Jupiter-3 focus shift works to your favor. Stop the lens down to F2.8 to use at infinity.

The Jupiter-3 is a nominal 52.4mm focal length +/- 1%. Lenses on the short side of the focal length will hold focus across the full distance range. If you get one of those, never sell it. Those in the middle- good out to 50m is doing well. On the high-side, these lose focus at 20m.
 
Sonnar Brian said:
At F1.5 do you have good focus at 50meters? Or stopped down to F4 or so, out to 50m?

Being out of focus used wide-open at 50m is normal. The lens has a longer focal length than the Leica standard 51.6mm. You can do 1 of 2 things: make the focal length shorter by grinding down the barrel to move the rear group in closer to the front. That takes a lot of work.

OR: this is where the "infamous" Sonnar/ Jupiter-3 focus shift works to your favor. Stop the lens down to F2.8 to use at infinity.

The Jupiter-3 is a nominal 52.4mm focal length +/- 1%. Lenses on the short side of the focal length will hold focus across the full distance range. If you get one of those, never sell it. Those in the middle- good out to 50m is doing well. On the high-side, these lose focus at 20m.
Click to expand...


Hahaha, ok, closing up the aperture actually did the trick.
Thank you very much Brian.
 
You are very welcome. I've used some 250 or so of these lenses, and have seen ones on the long side of the focal length. Those benefit from reducing the distance by 1~2mm.

Yours sounds fine, and ready for use.
 
Sonnar Brian said:
You are very welcome. I've used some 250 or so of these lenses, and have seen ones on the long side of the focal length. Those benefit from reducing the distance by 1~2mm.

Yours sounds fine, and ready for use.
Click to expand...

Brian, I have one last doubt, if I don't abuse of your kindness.
I am using and testing this J3 with my M240. Am I supposed to expect the same results on film? I have just got a Minolta CLE indeed, and wondering if focusing mods will affect this camera as well.
 
Film is more forgiving than Digital, it has thickness to it.

The distance scale of the lens can be used to check this. Focus the lens using the RF of the M240, which you know is accurate with the new shim. Note the distance on the scale. Now place the lens on the CLE, hold the camera where you held the M240 and focus on the same object.
 
I think, with J-3 been cheapest 50 1.5 in RF it needs to be kept easy.
Especially with black version which was reported to be not very sharp lens.
I have mine (silver one from fifties) shimmed in the middle between FED-2 and M4-2.

Here how it works on M-E 220 today.
All are f1.5.


Set on infinity (on my lens it is pass infinity mark)

50814417202_ca0d4096b1_o.jpg



Around 50m
50814417167_ef759df76f_o.jpg



Closer to MFD.
50814314206_253207fd4d_o.jpg

Focused on Pavarotti face and it is visible back focus.
 
Sonnar Brian said:
Film is more forgiving than Digital, it has thickness to it.

The distance scale of the lens can be used to check this. Focus the lens using the RF of the M240, which you know is accurate with the new shim. Note the distance on the scale. Now place the lens on the CLE, hold the camera where you held the M240 and focus on the same object.
Click to expand...

Hey Brian, does the Canon ltm 50 1.5 suffer from same issues on M bodies?
My J3 is driving me nuts, and I am considering to replace it.
 
Many Canon ltm 50 1.5 suffer from another disease - haze.
Originally it was caused in factory by wrong, aggressive lubricant.
After CLA it looks temporarily OK, but haze returns: slightly damaged, etched glass.
 
There must have been a batch of Canon 50/1.5 lenses with the caustic lubricants: I bought one missing the rear triplet, replaced it with one from a Nikkor.

My current "all-Canon" Canon 50/1.5: I've had for 15 years have not had to clean haze out of it. I have several Canon lenses that need to be cleaned often.

The Canon is built to the Leica standard. The two that I've owned were optimized for stop down use, I increased the shim to use wide-open. Focus is perfect across range.

Canon 50/1.5, close-up and wide-open,





At F1.5, distance.



On film- F2, I think.

 
Sonnar Brian said:
There must have been a batch of Canon 50/1.5 lenses with the caustic lubricants: I bought one missing the rear triplet, replaced it with one from a Nikkor.

My current "all-Canon" Canon 50/1.5: I've had for 15 years have not had to clean haze out of it. I have several Canon lenses that need to be cleaned often.

The Canon is built to the Leica standard. The two that I've owned were optimized for stop down use, I increased the shim to use wide-open. Focus is perfect across range.
Click to expand...

thank you sir
 
Sonnar Brian said:
There must have been a batch of Canon 50/1.5 lenses with the caustic lubricants: I bought one missing the rear triplet, replaced it with one from a Nikkor.

My current "all-Canon" Canon 50/1.5: I've had for 15 years have not had to clean haze out of it. I have several Canon lenses that need to be cleaned often.

The Canon is built to the Leica standard. The two that I've owned were optimized for stop down use, I increased the shim to use wide-open. Focus is perfect across range.
Click to expand...

By increasing the shim (of your Canon 1.5) you mean the one that sets the position of the lens in the focus mount, not any shims that might determine the distance between front and rear group? Because the latter would change the focal length, which is not necessary with a lens built to Leica standard, correct?
 
The Canon: I adjusted the shim that controls the optical barrel in the focus mount. The Canon 50/1.5 (nor J-3) use a secondary shim for distance between the rear group and front group.

No change in focal length necessary. (The Hybrid/Hacked Canon 50/1.5 with Nikkor 5cm F1.4 rear triplet, screwed into position and epoxied into place- it was free)
 
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