Photogrammetry for Archaeologists

Is there anything stinkier than the stinky smell of wet stinking permatrace?

Otherwise known as drafting film, the strong, durable and waterproof qualities of ‘permatrace’ make it an absolutely essential piece of an archaeologist’s recording kit.

But come to rain, even the tiniest splatter, and it smells like the rotting fish heads it was almost certainly made from. Bizarrely, some archaeologists have grown to love the fragrant whiff of ex-sea life – but not I – which is why DigVentures has been experimenting with new digital imaging technology (using a standard digital camera and inexpensive software) that may finally consign permatrace to the archives.

Using a series of standard 2D digital photographs, photogrammetry enables archaeologists to accurately deduce and model an object’s ‘point-cloud’ geometry. Once modelled, the same digital images used to create the 3D model can then be overlaid, creating a visually rich final product, far exceeding the level of information available from time-consuming hand-drawn survey records.

Photogrammetry has been used for many years in archaeology, but only recently has the technology become cheaply available. In our forthcoming masterclass – From Pixels to Point-clouds – archaeological photography maestro Adam Stanford will take you step-by-step through this new technology. We’ll be looking at examples of how we’re using photogrammetry on site at Leiston Abbey, creating models of objects as small as a coin find, as complex as a trench section, and as large as the Abbey itself.

Orthographic projection of Trench 4 (Leiston Abbey 2013 Season) derived from the 3D model, with the permatrace field-drawn section superimposed

Below we’ve embedded a model of the Abbey Church to get you started. This is a fairly low resolution model for demonstration purposes, allowing you to navigate around the ruins in your browser using your mouse to zoom in and out. The high resolution version is much more accurate, enabling 2D orthographic projections to be made of the building’s elevation with piercing accuracy.