Page 28 - TVH 2000 Anniversary Shipwreck Project

Data Acquisition Peter Holt Introduction The finds handling database 'Site Recorder' was developed using Microsoft Access 97 as it was readily available and easy to use. The relational database comprised 25 tables most of which were linked to the main artefact table. The main table in the database held information about the artefacts based on the unique artefact number. All the artefacts related to specific numbered dives, and the information about those dives was logged in a separate table. In order to speed up the registration of both artefacts and dives, a list of predetermined options was provided for the user to click on. To avoid inconsistency in descriptions, tables were created in advance to store the lists of full names, simple names and material. These were linked to the main artefact table so that only the listed words could be used, shown as a list of options when each filed was clicked on the form. New names could be added to the tables where necessary. The location and positional information was stored in a number of ways for each artefact. A location reference field recorded the position of the find within the site grid and a text description field could be used to give more detail if required. The position of the artefact given as co-ordinates could be added along with the acoustic positioning fix number. Dimensions were recorded along with details of completeness and condition. Some information about post-excavation treatment was included, but the details of conservation were left untouched. Provision was made for an in-situ image and a number of artefact photographs and a drawing within the database, these were hyperlinked to each artefact record. Further notes could be recorded as free format text. This allowed for an unlimited number of comments and revisions that could be added to each record in any order. Images Images relating to the site and the artefacts were obtained from a number of sources: • Digital stills camera • Diver’s helmet camera • Scanner • Hand-held video camera • Slides and prints The main source of images was from the Nikon CoolPix990 digital camera producing images of 2048 x 1536 pixels in high-resolution mode. The Superlite 17 diver’s helmet had a Chalco Eleven camera and light mounted on the top. This was mainly used to show both the archaeologists and dive supervisor what the diver was doing. The video feed from the camera was recorded on videotape along with the voice communications but it was also fed into a video capture card in the survey computer. Still images from the camera or from previously recorded tape could be captured using the card and recorded as 768 x 576 digital images. A CanoScan FB630U scanner was used to scan drawings, sketches, hull plans and text documents. Still images from a Panasonic SVHS hand-held video camera were also captured using the Hauppauge SVHS Video Magic video capture card. - 26 -