The Bronze Oak Project

Queen's Oak
Bronze Cast
H. 170 X W. 105 X 110 CM
BASE: 100 X 100 X 100 CM.

Facebook Twitter

Queen Elizabeth II and Adam Lowe, Director of Factum Arte. Her Majesty presented with the miniature version of the Signing Oak Tree at the Royal Academy of Arts, October 2016

The final miniature bronze oak tree on its plinth at the Royal Academy of Arts, London.

The final, miniature bronze replica of the Signing Oak Tree at Windsor Great Park


Ancient trees are part of our landscape, our art and our history. As remnants of the ancient wild woods, the oak tree inspires a sense of awe and mystery and is an enduring symbol of British identity. Britain has the largest number of ancient oaks in northern Europe. Most of them are found in its Medieval royal forests, such as Windsor Great Park and Sherwood Forest, where Kings and Queens have been custodians for over a thousand years: these are some of the largest and most astonishing living things that can be seen in the UK.

These thousand-year-old oaks represent a biological continuity dating back perhaps only seven generations to the last ice age. They are not only of historic interest but are also a valuable part of our cultural heritage (Ted Green, conservation consultant at Windsor Great Park and a founding member of the Ancient Tree Forum).

Ancient woodlands are one of our richest habitats, yet only fragments remain - and these remnants are becoming increasingly disconnected from the people that have helped to shape them. By the middle of the century it is predicted that 80% of the population will live in cities, and so this detachment from the natural world will only increase.

The project

The Factum Foundation for Digital Technology in Conservation, Factum Arte and the Bronze Oak Project are collaborating to create a better atmosphere in cities across the country.

The project´s central objective is to enhance the natural environment in cities for the benefit of local people by encouraging citizens to engage with it in a dynamic way: by ‘adopting’ a local oak and volunteering to plant new ones. The project aims to inspire and support a growing network of urban green corridors radiating out through British cities and into the woodlands beyond. The work carried out by the Factum Foundation covers both human and natural heritage and will aim to promote the project by creating and dotting exact replicas of the tree (as well as miniature versions) around cities in Britain.

The application of non-invasive / non-contact digital technology has made it possible to scan one of the oldest Oak trees at Windsor Great Park without damaging it. The nine-hundred year-old Signing Oak Tree was recorded at very high-resolution using close and mid-range photogrammetry (the data gathered is accurate to a millimeter).

So far, a miniature version of the oak tree has been materialised at Factum and donated to Her majesty the Queen of England to launch the project. As the Bronze Oak Project progresses, many more miniature versions of the same tree will be made - as well as its 1:1 facsimiles.

Recording & post-processing

On the 11th-16th April 2016, Pedro Miró, Manuel Franquelo, Ferdinand Saumarez Smith and Adam Lowe from Factum Arte/Foundation visited the site at Windsor Great Park and conducted photogrammetric recording of the 900 year old Signing Oak Tree.

Two Canon 5DSR cameras with two different lenses (a Canon 100-400 mm. & a Sigma 50 mm?.) were employed to photograph the whole tree. Each image was captured with a 90 degree overlap, in preparation for these to be stitched together using specific photogrammetry software.

Most of the tree trunk was recorded from the ground, and a cherry-picker was employed to record the branches from higher angles. Leaves and acorns were cast directly from life.

Adam Lowe, Pedro Miró and Manuel Franquelo carrying out photogrammetric recording

Recording the tree from a distance - two flashes were employed to even out the ambient light

The branches were recorded from the ground using two different lenses: a Canon 100-400 mm and a sigma 50 mm

Test scans with the Breuckmann 3D White Light scanner were also carried out by Factum´s Pedro Miró - however, the scanner was soon deployed for a combination of different factors which made it impossible to scan the tree at the desired resolution.

Tests were conducted with the Breuckmann White Light Scanner but the ambient light and the tree´s texture made it impossible to record the entire tree using only this method

Over 5000 50mb images were taken in total. The data gathered during recording was then stitched together using highly specialised software to create an accurate, digital 3D model using Capturing Reality´s RealityCapture software.

Post-processing the data

Post-processing the data creating a 3D model

The rematerialisation process

The miniature replica was made using a combination of digital and artisanal techniques.
3D Stereo Lithography (SLA), a form of 3D printing with Epoxy resin, was used to materialise the digital 3D model of the tree. The tree trunk´s 3D print was subsequently moulded in silicon and then cast in bronze using the lost wax technique in a centrifugal casting system at the Esfinge Foundry in Madrid, to replicate every possible detail.

External view of the miniature tree cast in wax

Runners on the interior of the wax cast

Parts of the mould employed for bronze casting using the lost wax technique

Adam Lowe & Sebastian Beyro observing the work in progress at the Esfinge Foundry in Madrid

Bronze oak tree - work in progress (details)


Comparing the original 3D print with the cast bronze miniature replica of the Signing Oak Tree


In October 2016, on the year of Her Majesty´s 90th birthday, the very first miniature replica of the 900 year old oak tree was presented to Queen Elizabeth II at the Royal Academy of Arts, London - to launch the Bronze Oak Project and to represent the Monarchy´s central role in the protection of oak trees across the UK.

Queen Elizabeth II at the Royal Academy of Arts, October 2016
Image© Red Photographic

This website uses cookies to improve your experience online. By using our website, you are agreeing to our use of cookies. To find out more, read our cookies policy. Close