2.5.1 Sy S t E M S r E q u i r i nG S t i t c h i nG
In the early days of digital panorama creation (the mid-1990s), the usual method was to
use a 35mm film camera equipped with a wide-angle lens, orient the camera in portrait
mode, and take a dozen or so shots while rotating the camera in roughly equal steps
through a 360° circle. With this technique, the camera should ideally be mounted on a
tripod and the camera’s position on the tripod should be offset so that the axis of rotation
passes through a point in the optical system (commonly termed the "nodal point" and
usually located somewhere through the body of the lens), in order to avoid or at least
reduce parallax. Photographers used either homemade camera-mounting brackets or
purchased specially designed tripod heads from commercial suppliers.
In its essentials, this method is still being used although as digital camera design and
capability have improved, film has fallen out of favor; today the overwhelming majority
of stitched panoramas are derived from born-digital images. Also, since the advent of
cubic and spherical panoramas, there is a need to shoot more than just a single row of
pictures around if the zenith and nadir of a scene are to be recorded.
A system for good-quality stitched output might consist of:
- Camera:
Preferably (but by no means necessarily) a DSLR model. The main advantage
of the DSLR design is the ability to use interchangeable lenses. - Lens
A rectilinear wide angle typically in the range of 14-24mm focal length (35mm
equivalent) or a fish-eye (either circular or full frame). Longer focal lengths can
be used; they will yield higher resolutions but require more pictures and a
lengthier stitching time; fish-eye lenses are widely used because a full scene
can be captured with a smaller number of shots.^4 - Tripod and panoramic tripod head
While some adventurous workers in the field have made very successful
hand-held panoramas, the use of a tripod and panoramic head really is
recommended.
2.5.2 Sy S t E M S n o t r E q u i r i nG S t i t c h i nG
Stitching can be a vexing and time-consuming process. Errors such as ghosting and
mismatched features require often difficult digital retouching and repair in an image-
editing application. As part of the stitching process, captured images almost always
require remapping from their rectilinear or fish-eye perspective to cylindrical or spherical
- However fish-eye images often need to be remapped to rectilinear projection, as some stitching
software will not otherwise work with them.