This document is intended to be a Guide to Good Practice for the creation and preservation of digital resources resulting from aerial photography (incorporating optical and infra-red imagery collected from an airborne platform), satellite and airborne remote sensing (using a variety of sensors), and archaeological interpretations made from such data sources. As most of the raw data sources considered in this Guide are commercial products, or are not created and managed in digital format, detailed archiving advice is not appropriate for many primary data sources. Instead, archiving guidelines focus on secondary data such as archaeological interpretations and mapping.
The hardware and software used to process, manage and analyse aerial photographs and remotely sensed imagery has evolved a great deal since the first ADS Guide was published and use of such datasets is commonplace and no longer solely in the domain of specialists. This Guide is therefore aimed at the non-specialist and is also not intended to provide information on how to interpret photographs or remotely sensed images, how to take aerial photographic images, or how to process such images once you have obtained them. General advice about locating and re-using original data sources is offered in Section 3. Throughout, this Guide refers to existing standards for documenting and cataloguing digital resources, and to the rich existing archaeological literature on these subjects. While the importance of standards is emphasised throughout the Guide, no single standard is prescribed. The aims of this document are more generic: to inform readers of the importance of good documentation practices rather than recommending how those resources should be documented.
As with the first edition, this new Guide starts with a brief review of the history of aerial photography and remote sensing, highlighting developments in digital products, and provides pointers to introductory reading. This is followed by a review of the types of data that are available or that can be generated by data creators. The core of this Guide consists of detailed suggestions on what to record in order to preserve and document a digital data set adequately, and where to look for most of the technical literature and other information resources. Additional sections provide details regarding commercial data providers together with standards commonly used in archaeology.
As highlighted elsewhere in these Guides, there is a strong trend for many digital technologies to merge and areas such as image processing, geophysics and geographic information systems (GIS) in separate guides. In particular, as most digital processing of aerial photography and remote sensing data in archaeology commonly takes place within the context of a GIS, this Guide will necessarily have some areas of overlap with the GIS Guide. We have attempted to avoid overlaps as much as possible and in many instances will refer you to the relevant guides for further details.