Stitching photographs into a panorama requires that the movement of the image pixels in between these photographs be of a simple pattern. Mathematically, a homography transformation is used to map pixels from one photgraph to another, and the same homography transformation accounts for the movement of all image pixels, and hence, the pixel movement pattern is "simple" and "global." In order to produce good panoramas, one needs to exercise some caution in taking pictures:

# Stand at a single location and just pan (left and right) and tilt (up and down) the camera to take pictures. I.e., use a "saw-tooth" pattern to rotate the camera in picture taking. Do not move (translate) the camera any other way.

# Make sure that adjacent pictures have large overlap.

# More often than not, a tripod is not needed - unless you want to construct a panorama of a small, tight place (e.g., inside a small room).

# Do not change any camera setting (zoom, focus, and aperture) when taking pictures.