298
IMAGE STITCHING
IMAGE DEVELOPMENT
Panoramic views can be created by “stitching,” or
overlaying, images side-by-side (see pp. 150–1).
Essentially, a sequence of images is taken from one
side of the scene to the other (or from the top to the
bottom). The individual images are then over lapped
to create a seamless composite.
You do not need special software to achieve
panoramas if the original shots are taken with care.
You simply create a long canvas and drop the
images in, overlapping them. However, small errors
in framing can make this a slow process, since you
must blend the overlaps to hide the joins.
Appropriate software
Speciality panoramic software makes joining up
component shots far easier, especially if they were
taken without a tripod. The available software
packages offer different approaches. Some try to
match over laps automatically and blend shots
together by blurring the overlaps. The results look
rather crude, but are effective for low-resolution
use. Other software applications are able
to recognize if the overlaps do not match and try to
accommodate the problem—some by distorting
the image, others by trying to correct perspective.
Many digital cameras are sup plied with
panorama-creation software.
For more unusual effects, experiment with
placing incongruous images together, or deliber ately
distort the perspective or overlaps so that the
components clash rather than blend. There is a
great deal of interesting new work still to be done.
299IMAGE STITCHING
Assembly
To start the assembly (left),
move the component
images into a single folder
where the software can
access them. With some
software, you will be able
to move images around to
change their order, while
in others you will have to
open the images in the
correct order. To merge
the images, the software
may need extra
instructions, such as the
equivalent focal length of
the lens used.
Final version
The component images
show very generous
overlaps, which make it
easier for the software to
create smooth blends. Once
the component images are
all combined on one canvas,
you can use the facilities
offered by the particular
software to blend and
disguise the overlaps to
create a seamless, single
image (below). Once you are
happy with your work, save
the file as a TIFF, not as a
JPEG, for best-quality results.
HINTS AND TIPS
A panorama resulting from, say, six average-size
images will be a very large file, so reduce the size
of the component images first to avoid stretching
your computer’s capacity.
If you want to create a panorama that covers half
the horizon or more, it may be better to stitch it
in stages: three or four images at a time, then
stitch the resulting panoramas. Keep an eye on
the image size.
Place all the component images together into one
folder: some software will not be able to access
images if they are in different folders.
SHOWING
AND SHARING
4

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