Alan Gillott (RDG Associates, York, UK)

The development of digital imaging technology allows the archaeologist considerable scope for manipulating, for good or ill, images produced from
cameras, of artifacts and excavations; X-Ray; LIDAR; and other geophysical
equipment. Images are also used as input to GIS and other forms of 2 and 3
dimensional representations yet very few of these tools incorporate metadata
in the composite output images.

Image metadata is poorly understood and only a select few understand the
difference between peer metadata and embedded metadata. Cameras routinely
add photographic metadata to their output yet archaeologists routinely rely
on peer metadata to describe the content, location and context of images.
Copying or distributing an image away from its home environment divorces it
from its context and puts the provenance of that image at risk. Proper use
of IPTC embedded metadata fields offer a mechanism for all archaeologists,
especially those without access to the funding required for having their
archives adopted for long term electronic storage, to simply and easily
identify their images and embed a basic description within the image.

Software manufacturers, particularly of X-Ray and other forms of imaging
equipment must be encourages to at the very least incorporate Exif data in
their output and GIS manufacturers must ensure that source images are
acknowledged in the metadata of output images. Web site developers should
also be aware that there are legal restrictions on removing metadata from
images yet by default metadata is removed from images displayed on web
clients.