[MF3D.FORUM:1120] Re: Sputnik focus fix

[Paul Talbot <ptww@xxxxxxxxx>]

"Harold R. Baize" wrote:

> I used the 
> technique that Brenda described (based on info from 
> Elliot S. and Tom D.). 

> It seems to have worked! The two lenses are about
> equally accurate. I now have confidence that I can
> adjust the focus on Sputniks. One change that I made
> to the described procedure was to tape actual Sputnik
> slide film to the film plane rather than marked acrylic.

That should work provided you can be sure the film is
being held at the same point it would be with the
camera backs closed.  That can be tricky.

> I then set it on a light box. Worked well for setting
> the focus. I used an SLR with a 50mm lens (only one I
> have) and that may have set the focus off a bit.

A longer lens would be more precise.  The longer lens
would have less DOF, so you could be more confident
that you really hit the focus spot-on.

> I was
> not clear on how to use the technique on the view finder,
> which may account for the distance settings not matching
> the focus.

There are two issues regarding the view finder.  First, it
must be in focus synch with the two taking lenses.  If you
have already set the left and right lenses, you may find
that trying to set the center lens disturbs the work you
already did on the other two.  Second, the viewfinder focus
must be in agreement with the distance dial.  Luckily the
distance dial can turn independently of the lens front
element, so it's simply a matter of setting the camera to
focus on an object at a known distance, then aligning the
distance dial to agree.

I previously wrote:

> Any good local camera repair person should be able to
> handle it.  If you have a problem finding one to work
> on it, contact me off-list.

I have an off-list report from a subscriber who was able to
have the work done by a local camera repairman, at a cost
of only $35.  So if any lurkers are disinclined to attempt
this because it sounds tough, you may find you can readily
have it done by a local repairman at a reasonable price.

Paul Talbot