NOVOFLEX VR-System III Manual page 5

fig. 1
fig. 3
Now you have found out the right distance on the focusing rack:
Floor lamp and door frame don't move to each other even though
you are panning the camera! With this setup you avoid all parallax
effects.
Write down these settings for future exposures with this camera-
lens-unit. For this purpose read off the values given by the indica-
tor scale at the focusing rack.
Preparatory step 5:
Forward-Backward Adjustment:
Mount the lens, whose nodal point you want to find, to the camera body.
When using a zoom lens, set the required focal length.
Look through the viewfinder. Find a vertical edge or line, such as a floor lamp,
which is located in the foreground and bring it in line with a vertical object in
the background e.g. a door frame or an edge of a building. You may have to
move the tripod for this purpose. Now pan the camera from right to left and
back while looking through the viewfinder. When the two vertical lines move
to each other (see fig. 1+2), you are outside the nodal point. When they stay
together (see fig. 3+4), you are inside the nodal point.
fig. 2
fig. 4
In this example I brought the floor lamp in line
with the door frame (fig. 1). When I panned
the camera to right, the floor lamp moved to
left in relation to the door frame (fig. 2). This
is an indication of rotating outside the nodal
point of the lens.
Advice:
If your camera is equipped with a depth of field
preview, use it while you are looking through
the viewfinder and close the aperture, so that
you have the maximum depth of field.
Now set another distance on the focusing
rack. When panning again you will notice that
the movement of the lines to each other will
either be stronger or weaker. In the last case
you shifted the focusing rack in the right di-
rection. Repeat the procedure until the vertical
lines stay side by side (see fig. 3+4).
Now the whole system is panning in the nodal
point of the lens.