In July 2024, James and Pat from Heritage360 travelled to Iron Acton, near Bristol, to carry out digital recording of a Tudor manor as part of Henry on Tour. North of the village stands Acton Court, a wonderful example of a Tudor house with a tantalising past. In 1534 Nicolas Ponytz, its owner, expanded the manor house with a magnificent East Wing. This is believed to have been for the pleasure of Henry VIII and Anne Boleyn, who were due to visit as part of the 1535 progress (you can read more about this in our blog piece Henry VIII at Acton Court - for one night only)
The 16th century represents an important period in Acton Court's its development when maritime trade played a significant part in the family's fortunes. Some intriguing aspects from this time survive today, including names from the Ponytz family etched into a windowsill, and a variety of scratched graffiti left by various visitors to the house. These include sailing ships, which were drawn to such a level of accuracy that it has been suggested that they could only have come from those who knew ships intimately.
Background of technology
Heritage360 uses structured light scanning to digitally record and capture the surface geometry of buildings and artefacts. The scanning equipment includes the Artec Leo and Artec Space Spider (I & II) – small, hand-held devices that can record data with a precision of up to 0.05mm, the width of a human hair! The scanners work by rapidly projecting stripes of light onto a surface and then detecting any distortions created by variations in the surface, such as scratches and bumps.
The range of scanners allows us to capture objects varying in size from just two to three centimetres up to around three metres. We can also capture data from a wide range of materials, from stone, wood and metal through to textiles. A limitation of structured-light scanning is that highly reflective or transparent surfaces can create digital 'noise' and make it hard to capture some types of data, such as those that have glossy coatings or glass elements.
At Acton Court the scanners were used on stone and plaster surfaces to capture the graffiti, which could be found on many walls and surfaces. Stone materials are captured particularly well because of how the textured surfaces interact with the scanner's projected light.
Our methodology
Along with the accuracy of data, speed is a significant factor when recording on-site. The scanners can capture roughly a metre square surface (e.g. walls, floors, etc) in just a matter of minutes, allowing the capture of a couple of dozen scans in a single day.
A typical set-up on site will normally include two stand lights, a laptop, and the scanners themselves. If access to elevated or other hard-to-reach areas is necessary, we may also require ladders or access platforms. When operating in sensitive historic environments, we need to ensure that our working areas are safe and secure. This ensures data can be collected quickly and efficiently, but most importantly it protects other site staff (and indeed the public if the site is generally accessible) from cables and other trip hazards. We also need to ensure that those with photosensitivity-related conditions are aware of the scanners' flashing lights and can keep a safe distance away if necessary.
The additional stand lights are used to create an even, distributed light that minimises shadows cast over the areas to be scanned. Shadows can affect the scan quality, but most notably they appear on the photographic texture that is captured alongside the scanned surface geometry.
Whilst the Artec Leo is completely self-encapsulated, the Artec Space Spider – our highest resolution scanner – requires a tethered cable connection to a laptop. This enables a large quantity of data to be captured and stored simultaneously, but it also allows both the scanner operator and the site team to watch on-screen the scan build up in real-time.
Outputs
Whilst capturing the scans on-site can be a relatively rapid task, processing the scanned data into a usable digital model can be a time-consuming operation. A low-level process stage is often conducted briefly on-site to verify that the scan has captured the subject in a suitable quality, but longer, more in-depth processing is conducted at our offices at the University of York on powerful workstation computers. This deeper processing stage removes the digital 'noise' that is frequently captured alongside the 'real' data, and also helps to fill in any small areas that the scanner could not capture.
Once processed, the scanned data can be output as a digitally accessible model, which can then be uploaded to platforms such as Sketchfab where viewers can engage and interact with them. Associated information for objects can be displayed here alongside links to related projects and organisations, making such platforms fantastic tools for presenting data widely and making sometimes delicate or sensitive objects accessible. See below for two examples.
3D scanning is just one part of the Henry on Tour project's digital strategy. Another element that was also deployed at Acton Court was an interactive virtual tour using the Matterport platform that allows viewers to navigate through the site and access information about key areas and features... including many of the 3D scans! It is hoped that the 3D scans will offer an interesting additional perspective on a property with a rich Tudor history.
