Photogrammetric Examples

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Wessex Archaeology has undertaken a wide range of photogrammetric surveys, including aerial and terrestrial topography, Historic Building Recording, underwater wreck survey and small finds recording. Our resources include high-end digital cameras, a comprehensive suite of professional photogrammetric software, a bank of dedicated geomatics workstations and a full range of 3D modelling software for producing high-quality stills, videos and reconstructions. 
 
For a selection of case studies choose from the links below or right.
 
 
For the full range of geoservices services click here
 
 
 
 

Rubha an Fhaing Duibh

1361 EDM survey for accuracy analysis

In April 2012 Wessex Archaeology was commissioned by Forestry Commission Scotland to undertake a detailed measured archaeological survey of Rubha an Fhaing Dhuibh, a suspected Iron Age promontory fort located on the southern bank of Loch Shiel, near Glenfinnan. In consultation with Forestry Commission Scotland it was decided to use the survey as an opportunity to test out the photogrammetric workflow under development in Wessex Archaeology.
 
For the survey we took over 2,000 digital photographs over the course of a single day. The camera locations were not recorded in the field in any way but were worked out by the photogrammetry software in postprocessing. This allowed for data capture to be undertaken in a matter of hours. We also spent another full day surveying the site using a Total Station. The resulting photos were all loaded into the automated photogrammetry software VIsualSFM (currently under development by Changchang Wu of the University of Washington) in a single batch and processed on a dedicated geomatics workstation. This required over a week of computer processing time!
 

1362 40 million points generated from the photogrammetric survey

The result of the data capture at Rubha an Fhaing Dhuibh was a point cloud of over 40 million coloured vertices. The point cloud was then used to generate a highly accurate series of plans and elevations of the site and included some areas which were under water! 
 
 

Drumbeg Wreck

1364 Cannon recorded using multi-image photogrammetry

In 2012 Historic Scotland commissioned WA Coastal & Marine to survey a historic shipwreck near Drumbeg in the north-west Scottish Highlands. The wreck was found by local divers Ewen Mackay and Michael Errington while scallop diving close to the village of Drumbeg. 
 
WA Coastal & Marine were commissioned to survey the site and found that it consisted of three heavily encrusted cannons with evidence of a preserved wooden hull beneath them. A number of artefacts have also been recovered from the site including cannonballs, galley bricks, a wooden rigging block and a delft tile decorated with an image of a sailing ship. The exact date and origin of the ship is still unknown but the evidence points to a 17th / 18th century date. 
 
 
On the 18th March 2013 Fiona Hyslop, Cabinet Secretary for Culture and External Affairs announced that the wreck has been designated as the first of Scotland's Historic Marine Protected Areas. This designation recognises that the wreck is a historic asset of national importance. The designation of the wreck at Drumbeg lasts only for a period of two years, during which time a consultation will invite views on proposals to make the designation permanent.
 

1365 3D survey data was used to generate reconstructions

One of the most exciting aspects of the project was the chance to apply our expertise in multi-image photogrammetric recording in a marine environment. Digital photographic recording of the wreck site was undertaken as part of a single dive, taking around 20 minutes altogether. This data was processed on our dedicated geomatics workstations over several days. We used the resulting high-quality 3D models to enhance our site plans and also to create animated reconstructions of what the cannons and anchor would have originally looked like. 
 
Associated Links:
Drumbeg Report
BBC News
 

Lewis Chessmen

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This scan is of a replica night from the Lewis Chessmen, a set of 93 gaming pieces found on the Isle of Lewis in 1831. The chess pieces are carved from walrus ivory and whale’s teeth and are thought to be Scandinavian in origin. Some are held in the British Museum and some in the National Museum of Scotland.
 
The knight wears clothes which date to the 12th or 13th century. His coat is split at the front and back and he holds a kite-shaped shield, a lance and wears a conical helmet.
 
This replica was scanned as part of a benchmarking exercise undertaken at Wessex Archaeology to test and demonstrate the value of multi-image photogrammetry for accurate recording of small artefacts. The model was generated from 60 photographs and has sub-millimetre accuracy.
 
Click on the image below to see the 3D model in action.
 
Not working? In order to view this 3D interactive model you will require an up to date browser and for WebGL to be installed/enabled – see http://p3d.in/faq/systemspecs for more detail. At present WebGL is not well supported in Internet Explorer but it is in Google Chrome
 
 
 
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The Old College, Aberystwyth

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Wessex Archaeology Wales has undertaken a photogrammetric survey of The Old College, Aberystwyth, one of the town’s most striking buildings. A total of 222 photos were taken with a standard digital SLR, which were then processed to produce a 3d model from which accurate orthographic projections can be taken.
 
The first building on the Old College site was Castle House, designed in the late 18th century by John Nash as a summer retreat for Uvedale Price, famous for his championing of the Picturesque approach to landscape design. This three-sided building was built atop a low cliff directly overlooking the sea.
 
In 1864, the site was developed by the Victorian railway entrepreneur Thomas Savin, who employed the architect John Pollard Seddon to incorporate the house into a larger hotel built in the Early English style. Savin’s intention was for his Castle Hotel to accommodate the many middle class visitors he believed the railway would bring to the area, but having spent £80,000, and with the hotel only partly opened, he went bankrupt in 1866.
 

1733 Rectified photos and initial model

 
 

1734 North western elevation of Old College, Aberystwyth1735 Gothic porch

The following year, the hotel was bought to house a proposed new University of Wales, and Seddon was again employed to undertake the necessary works. When  the north wing was gutted by fire in July 1885, Seddon convinced the University that restoration would be cheaper than building anew, and further works were undertaken by Seddon and Coates Carter in 1887–9.
 
At the same time the south range was rebuilt as a science block in a more plain Gothic style, with a circular tower at its end bearing a mosaic triptych, by C F Voysey, showing Archimedes being presented with models of modern technology –a steam locomotive, and a steam ship with its sails also set. Two gargoyles above a door show Science defeating Error, and Light overcoming Darkness.
 
When the costs of Seddon’s works spiralled he was replaced by Charles Ferguson, who not only completed the works, but then added a four-storey range in the Gothic style, completely replacing the original Castle House.
 

1736 Gargoyle: Science defeating Error

The Old College is still owned by Aberystwyth University, which uses it predominantly for administrative purposes. 
 
 

Scottish National Portrait Gallery

One of the major advantages of multi-image photogrammetry is that it can be applied to subjects of any scale. Using exactly the same camera and workflow we applied for the Lewis Chessman we carried out a rapid survey of the Scottish National Portrait Gallery, next door to our Edinburgh office.
 
The survey was conducted in less than ten minutes on the 25th October 2013, using a compact handheld camera and processed on a Wessex Archaeology geomatics workstation. The technique is faster and more accurate than traditional rectified photography and can be used to create accurate orthographic projections in less time and for a lower cost than laser scans. 
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