Nodal Point (continued)
Step 2: Fore-Aft Adjustment
This step is most easily accomplished
out of doors. Find a vertical edge or
line, such as a doorway or edge of a
building. Position your camera and
tripod about 2-1/2 feet away, or as close
as possible with the edge still in focus
when you look through the
viewfinder. If you’re using a multirow
head such as the QuickPan III
Spherical, set the swing arm to a level
horizontal position (zero degrees).
Looking through the camera’s
viewfinder, find another vertical edge
or line that is far away, such as another
building or telephone pole. Align the
two objects and rotate the pan head
so they are in the left hand side of the
viewfinder.
Rotate the pan head so the two
objects move over to the right hand
side of the viewfinder. Unless you’ve
managed to unwittingly locate the
right position, you should notice the
two objects will move with respect to
each other as you rotate the pan from
If, as shown above, the two objects move with respect
to one and another in the viewinder, slide the camera
fore or aft in order to eliminate this movement. Here,
the telephone pole has moved behind the brick wall.
left to right. Slide the camera to the
front or rear as required to eliminate
this relative movement.
Step 3: Record Your Results
After you’ve discovered the two
location dimensions, be sure to record
the settings. The QuickPan III has
convenient indicator scales for this
purpose. These numbers represent
the nodal point for this given camera
and lens combination. If you change
cameras or lenses, this procedure may
have to be repeated
Step 5: How About Rangefinder
Cameras?
A rangefinder camera is a camera
where you look through a separate
viewfinder and not through the
actual lens. The process is basically the
same. Locate the Side-to-Side
adjustment as discussed in Step 1.
When it comes to the Fore-Aft
adjustment, you won’t be able to look
through the viewfinder to determine
What is it and how do I find it?
Looking through the viewfinder align a close object (brick
wall) with a faraway object (telephone pole). As you rotate
the camera from side-to-side there should be no relative
movement between the two objects as shown to the right.
