Shooting Panoramas
How much Overlap?
The amount you turn the camera for each
shot varies. It is dependent on a number of
factors such as the field of view (the angle)
of your camera and lens, as well as which
program you intend to use. For example, with
iSeeMedia PhotoVista, VR Toolbox VR Worx or
Apple's QuickTime VR Authoring Studio, the
recommended image overlap is anywhere from
one-quarter to one-half. That’s a good rule
of thumb for most stitching applications. You
should check with the recommendations of
the software that you intend to use in order to
determine overlap requirements.
How many Shots?
Once you’ve determined the overlap, you’ll be
able to figure out how many shots. The easiest
way to do this is to simply look through the
viewfinder and turn the camera to achieve the
desired amount of overlap. You then check the
angle readout to see how far you turned the
camera. Round the angular value to the nearest
convenient value. For most stitching programs, it
is generally not that important to use a precise
overlap value. However, it should be noted that
some programs are more sensitive to an overlap
value that constantly repeats from shot to shot.
You may need to experiment somewhat to
How do I begin?
obtain the best results.
Taking the Photos
When you’re ready to shoot, make sure that the
camera is securely attached to the KiWi. You
should use a tripod that is sturdy, ideally one
that has a center support system of braces to
help keep the camera from flexing.
Proper leveling is important and often
misunderstood. When it comes to leveling
there are two things that are fairly important.
With multirow panoramas (i.e. Realviz
Stitcher) the issue of leveling is less crucial and
primarily involves aestethics and placement of
the horizon. We’ll concentrate primarily on
cylindrical or single-row panoramas.
First, the camera's optical axis should be parallel
with the rotation plane of the tripod head. In
other words the camera should not be pointed
up or down with respect to the plane of
rotation.
Secondly, it's also somewhat important for the
camera and film/CCD to be properly aligned
with respect to rotation when viewed from the
front (looking into the lens).
This can happen because the camera is not
seated flush against the upright bracket. This
is pretty common since many cameras have
mounting screws that are not in the center of
the base. Many cameras have screws off to one
end of the camera or at the edge of the camera
and this can cause the camera to not be pulled
down evenly onto the tripod head mounting
plate.
Another problem is that CCDs may not be
accurately positioned within the camera body
and respect to the mounting surface. It only
takes a fraction of a degree and, with other
manufacturing tolerances, this can add up to be
noticeable.
This misalignment can also happen if the upright
bracket is bent or is not exactly perpendicular
to the rotation plane of the head. At Kaidan we
check this dimension very closely to ensure it's
as close to 90° as reasonbly possible.
The effect of a rotated camera (when viewed
looking into the lens) is a stairstepping of
images as you progress around the panorama.
Stairstepping has nothing to do with the state
of the entire head being level with respect to
the horizon. This can be corrected by rotating
all the images a slight amount in your authoring
program.
You can also shim the camera/head to
compensate for such misalignment errors
as well. A few layers of tape is usually all that
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