R-D1 RF alignment 101

[tmessenger]

Update: I started this whole process with a lens that I thought was collimated @ infinite, it was not. I did get my finder adjusted with a correctly collimated J8 and it now focuses correctly @ 1M and infinite.

I decided to pop the top on my new refurbished RD1 and see what all the excitement was about regarding RF alignment. I first tried adjusting the vertical and horizontal alignment with the screws accessible through the hot shoe but could not get the infinite focus to come in so I decided to get more into it. For infinite the superimposed (movable image) needed to come more to the right to align with the fixed image but the horizontal adjusting screw was not getting it. I talked with Don at DAG about this and he said to try the center screw, this turned out to be the ticket as this center screw moves the image right to left. The two small screws are eccentrics and ride in slots and move a small lens either side to side (center screw) or back and forth (horizontal screw), the vertical screw moves the lens more in a up and down direction. Unfortunately the lens does not move in true straight parallel or vertical paths, these eccentric screws can move the lens at somewhat of an angle. This means when you change one setting say side to side it effects the lens fore and back, so you have to keep working each screw a little at a time to arrive at the desired lens placement / finder alignment. After I got infinite focus aligned I checked close focus (1 meter) and it was now out. This require adjustment to another eccentric screw on the left side of the finder box and after I got close focus dialed in I had to go back and touch up infinite focus. You just have to go back and forth a few times until you get both infinite and close focus working together. I can now see why these cameras can come from the factory with alignment problems. It does take some time to get the 4 adjustments coordinated and once the tops in place it's some work to get it back apart to make corrections.


Tim

 

[mountainrivera]

So are you saying that even a vertical alignment requires you tinker with more than just the one screw?

Thanks

 

[tmessenger]

So are you saying that even a vertical alignment requires you tinker with more than just the one screw?

Thanks

The vertical adjusting screw as far as I can tell is the exception it moves the floating image top to bottom and I don't believe it has much effect on the other adjusments.

The thing is the RF adjustment is not as smiple as focusing a camera lens. The adjustment is 3 dimensional, top to bottom, side to side and fore and aft. All the adjustments have to come together to get a clear registered RF patch. So if more then just the vertical is off you have to get more into it.

Regards,

Tim

 

[pfogle]

Tim, what lens are you using to assess the close focus?

 

[B&W Norway]

So are you saying that even a vertical alignment requires you tinker with more than just the one screw?

Thanks

It does require more than one screw!
You need to do corrections in close and infinity focus as well, because they all influence a bit on each other.

So it will take some time.

I did it by removing the hot shoe

 

[tmessenger]

I'm using a Jupiter 8 that was collimated for Leica bodies by Brian Sweeney. Note: I did some checking for the correct registration/coulping distance from the lens seat to the cam and this lens is within those specifications. The trave distance from infinite to 1 meter on Leica lenses is 3mm. I'll finded out today if all is well when I put the top back on and do some test shots.

Tim

Tim, what lens are you using to assess the close focus?

 

[tmessenger]

"I did it by removing the hot shoe."

The problem is the close focus eccentric is not accessible without removing the top. I think it just depends on how far out the alignment is but just touching up the vertical should not cause any trouble with the other settings. If you have other mis-alignments to start with and think adjusting the vertical is going to take care of it you're going to be disappointed.

Tim

I did it by removing the hot shoe.

 

[jlw]

In my experience, you also can do SMALL infinity-position adjustments without having to adjust the other screws.

You can think of the small screws for horizontal and vertical adjustment as fine-tuning controls -- for minor touch-ups, they should be all you need.

If you need to make more drastic adjustments, you need to be prepared for several rounds of adjusting everything, as the original post explains. However, that's par for the course for most RF cameras.

 

[tmessenger]

I put some Russian lenses on my camera today and did some tests. With the finder correctly adjusted @ 1m and infinite the lenses did not agree with the finder at 1m, they were front focusing. I did some more 1m test shots and moved the lens so it was in focus at 1m (it now shows more like 1.1m on the distance scale) then reset the finder to agree with lens. Now the infinite focus was not aligning in the finder, there was no way to get it adjusted so the finder was correct at both infinite and 1m. I did some more serious measurements to verify the travel distance of the lens cam going from 1m to infinite and using my dial indicator it measures around 3.1mm on all the lenses and there's the problem. The travel distance specification I found for Leica lenses is 3mm.

The lens that was collimated by Brian Sweeney is in focus @ infinite but that doesn't change the cam ratio.

Tim

 

[pfogle]

Tim - I've just posted a new thread which refers to this issue. You can't get a good adjustment with a Russian lens.