Nodal Point
This is one of the most frequently
asked questions when it comes to
stitcher-based panorama creation.
Once you understand the basics, you’ll
be able to easily locate the nodal point
for any camera and lens combination.
Simply put, the nodal point is the point
inside your camera where the light
rays converge and flip over. When
shooting a panorama it’s necessary to
rotate about this point to eliminate
the image mismatch caused by parallax
error.
It’s also worth noting that the nodal
point is not the same as the film
plane, which is often marked on
the underneath side of many 35mm
cameras. Generally, for most 35mm
cameras and lenses, the nodal point
is located somewhere towards the
center of the lens barrel.
Parallax error can be easily
demonstrated by this simple
experiment. Close one eye and hold
your index finger upright about six
inches away from your open eye.
Rock your head from side to side.
Notice how your finger moves with
respect to the background. This
relative movement is due to the fact
that you’re not rotating your head
around your eye’s nodal point, which
is somewhere in the center of your
eyeball. Instead, you’re rotating about
your spine which is several inches to
the rear and off to one side. It is this
relative side-to-side motion that we
will strive to eliminate when setting up
a camera for VR panoramas.
Step 1: The side-to-side adjustment
Once your camera is fastened to your
camera bracket, move to the front of
the tripod head so you’re looking into
the lens. Adjust the camera bracket so
that the center of the lens is directly
over the pivot axis of the tripod head.
Try to be as accurate as possible. You
should strive to get this adjustment
within plus/minus a 1/16th of an inch.
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.
Looking through the camera’s
What is it and how do I find it?
Parallax error can be easily demonstrated. It’s the relative move-
ment caused by a shifting point of view. In this example, you eye
is moving with respect to your hand and the background.
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