Three areas were selected for excavation, each designed to recover evidence regarding the nature and chronology of different magnetic anomalies and permit an assessment of the levels of plough-damage and the degree of protection provided by blown-sands within the single field. Trench 128AA was situated over three features with the characteristic anomaly given by Anglo-Saxon Grubenhäuser. The second area, Trench 128AB, was situated to investigate a number of small ring-ditches that were appearing in large numbers in the geophysical surveys, reflecting a widespread distribution immediately to the south of the ladder settlement. The third area, Trench 128AC, was designed to cut across the east-west aligned ladder settlement with a view to assessing the level of preservation of the archaeological deposits and the chronological range of the features encountered. In each area the objectives for excavation combined a need to assess the level of preservation and the need to clarify the nature of the features that showed so well in the geophysical survey.
The research objectives relating to digital recording were applied across all trenches. This drew upon established recording practice applied by the Landscape Research Centre (LRC) since 1984. Additional experiments were determined by the availability of new technologies, which in the case of the survey aspects were only made possible with the support of the survey team at the English Heritage Centre for Archaeology (CfA).
Excavations in Heslerton from 1984 to 1996 had used handheld computers in the field to record Context and Object data as standard practice. A variety of devices had been used, including Sharp PC1500 and PC1600 handheld devices with a one-line display. These continued to be used for recording objects until the close of the excavations in 1995/6, although by this time the Context Record had been transferred onto Hewlett Packard MSDOS compatible handheld computers. The small memory capacity of these devices meant that much of the record was compiled using numeric codes, which were quick to enter and required minimal storage. Likewise, the LRC object record used numeric codes to cover most fields, and benefited from the fact that for more than a decade one individual undertook most of the recording.
During 2000, following the purchase of a Handspring PDA, the LRC recording system was transferred to the Palm operating system, supported by the Handspring using the Think DB database package. This proved both easy to use and fast, employing pull-down lists where we had previously used numeric codes, and allowed for free text entry using a stylus and the shorthand character entry system, 'graffiti', employed by the Palm operating system. An appeal for sponsorship was made to the Handspring Foundation who donated a number of PDAs for use in the project. The only change to the context record resulting from this transfer was the increasing freedom to use longer text in the notes field, where in the previous system these had been restricted by machine memory to short condensed notes. The record structures are discussed in detail below.
Improvements in digital cameras meant that by 2001, the Fuji S1 Pro camera was one of a breed of new Single Lens Reflex (SLR) digital cameras, which, for the first time, supported resolutions that offered the potential to record imagery that could compete with a conventional film-based SLR. Digital cameras supporting a variety of resolutions were used in the field to compare the potential of the results from each with conventional 35mm and 6x6cm film images recorded using Olympus and Hasselblad film cameras. It was felt at the outset of the project that digital cameras offered the potential to replace the use of Polaroid film, which was often used in the past for quick record shots that could be linked to the written record.
In addition, digital photography experiments were also designed that employed digital video technology to document general progress and develop resources that could be downloaded from the web.
Since the mid 1980s at Heslerton, all objects, artefacts and ecofacts have been individually recorded, including a full 3-D location at one centimetre precision. For the purposes of this project we continued to record finds in the same way, using our relatively ancient Electronic Distance Meter (EDM) with a separate logger programmed for the purpose of recording location information for all contexts, finds and drawing reference points. At the same time we were able to evaluate the potential of new robotic and reflector-less instruments with in-built memory cards for on-site recording.
Field survey has been revolutionised by the development of GPS technologies, and part of the project was designed to assess this technology when applied to excavation. Experiments targeted at field survey on foot and by vehicle, were evaluated for the production of high-precision surface survey.
One area that prompted most discussion was the potential for using digital techniques for planning and surveying. In Heslerton, the plans and sections drawn in the field are subsequently digitised either as scanned images or as vector-based drawings. This has been common practice for well over a decade, and is common in most other excavations using extensive digital post-excavation programmes, It seemed that the project would provide a good test-bed for alternative methods of generating site plans using either the Total Station, the GPS, or direct digitising using an in-field digitising pad linked to a PDA.
Among the digital research objectives was the desire to determine to what extent and at what level daily updates could be maintained on the Web and what level of resource this might entail in a larger project. With an increasing emphasis on digital data generation in the field, it was felt there was some value to be had in determining, for instance, whether there was potential or benefits to be gained from maintaining an offsite archive that could be added to or examined directly from the field using mobile phone-based technologies.
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Last updated: Wed Nov 11 2009