Nikon SP half-mirror prism needs factory adjustment

Imakebadphotos

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So, a few months ago I came on here talking about my Nikon SP's rangefinder being out of alignment, more specifically it can focus closer than 3ft even though it is perfectly focused at infinity. I sent it to DAG and was sadly told that the factory tolerance of the half-mirror prism was tampered with sometime in the camera's lifetime and that he could not re-adjust it. My question is, are there any repairmen that can realign the prism back to its factory tolerance? Can that even be done or am I out of luck.
 
I'd probably ask Kiitos before Kanto, and yes, they're likely your only options if DAG can't help.
 
I sent it to DAG and was sadly told that the factory tolerance of the half-mirror prism was tampered with sometime in the camera's lifetime and that he could not re-adjust it. My question is, are there any repairmen that can realign the prism back to its factory tolerance? Can that even be done or am I out of luck.

The half-mirror prism, which is that little piece of glass on the left in the photo below, is fixed in place at the factory. There is no tolerance adjustment you can make with it. Assuming nothing has been broken, it has to be repositioned then reglued in place - a very difficult task to perform without the right equipment, and no repair place is going to have the right equipment. I wouldn't get my hopes up, but agree that Kiitos and Kanto are probably the only places that would touch it. Only way to find out is ask. I'm not sure about Kanto, but knowing the guys at Kiitos I think they would swap out the finder if they had a spare lying around (unlikely) rather than attempt a repair though.


Nikon SP rangefinder assembly by Jon, on Flickr
 
The half-mirror prism, which is that little piece of glass on the left in the photo below, is fixed in place at the factory. There is no tolerance adjustment you can make with it. Assuming nothing has been broken, it has to be repositioned then reglued in place - a very difficult task to perform without the right equipment, and no repair place is going to have the right equipment. I wouldn't get my hopes up, but agree that Kiitos and Kanto are probably the only places that would touch it. Only way to find out is ask. I'm not sure about Kanto, but knowing the guys at Kiitos I think they would swap out the finder if they had a spare lying around (unlikely) rather than attempt a repair though.

Nikon SP rangefinder assembly by Jon, on Flickr

Yikes, makes me wonder how someone could have disassemble that in the first place. I will send both of them an email to see if it is even possible to fix. But if the worst is to be true, then this camera is lost and I guess it's time for me to hunt for another one.
 
Yikes, makes me wonder how someone could have disassemble that in the first place.

I suspect a bodged cleaning attempt caused the problem. Many vintage SPs have faded focus patches that can be improved considerably by cleaning the half-mirror prism (especially the hard to access 45 degree surface). But its a delicate operation and its hard to get at the half-mirror prism with the finder in the camera, and if too much force is used this kind of problem can be the result.

Worst case scenario, stick a 21mm lens on your SP and scale focus!
 
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