[MF3D.FORUM:1133] Re: Sputnik focus fix

["Don Lopp" <dlopp@xxxxxxxxxxxxxxx>]

Sputnik focus first $35 seams a bit high to me, in any event  it is best to
determine focus at infinity, not at any inter mediate distances because of
depth of focus problems.
----- Original Message -----
From: "Paul Talbot" <ptww@xxxxxxxxx>
To: "Medium Format 3D Photography" <MF3D.Forum@xxxxxxxxxxxxx>
Sent: Saturday, August 19, 2000 11:29 PM
Subject: [MF3D.FORUM:1120] Re: Sputnik focus fix


> "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
>