Metric Condition Records: Does the Capture Method or the Information Need Determine the Performance of 3D Heritage Records?

The interdependency of our questions about the historic environment and the data capture techniques used to answer them is complex. Metric survey is a primary tool that, directed correctly through brief and specification, can provide useful data for the heritage information process. The inherent differences in data quality derived from different techniques are primarily a result of capture by two classes of information: undifferentiated (derived from indirect techniques such as photogrammetry and laser scanning) and differentiated (derived from direct techniques such as measured drawing, total station, and global positioning systems [GPSs]). The value and utility of information is thus dependent on the method chosen for its capture; it may demonstrate selectivity to meet a particular purpose or be an unselective record for future interpretation. An appropriate response to information requirements should be shaped by an understanding of the significance and value of the heritage (as described under Article 16 of the ICOMOS Charter of Venice, May 31, 1964) to be recorded along with the performance of capture techniques.