Tag Archives: Petrie Museum

How will we record the printing plates, stamps and rollers? Brief introduction to 3D imaging technologies

A couple of weeks ago, we introduced our 3D scanning project, Stamp printing plates, dies and rollers: from vault to view, in partnership with UCL. Mona Hess, Research Associate and PhD candidate at UCL, is the 3D specialist for this project. Mona has been working with museums for the past 10 years, creating three-dimensional digital models and physical replicas through 3D printing (such as these busts of Darwin and James Watt). She is interested in opening up archives and collections, giving visitors access to hidden objects. In this post she will introduce the different techniques we will be using to capture some of our hard-to-photograph philatelic material.

The BPMA’s philatelic collection goes far beyond stamps. It also includes plates, stamps and rollers, all of which are difficult to photograph. Many of these objects, especially the plates, rollers and dies can’t be on display to the public. There are conservation and security issues that prevent them from coming outside of the vaults. Despite this we still want philatelists, researchers, enthusiasts and visitors to be able to see and interact with these objects digitally.

Mona Hess face to face with the 3D digital model of Mrs.Flaxman

Mona Hess face to face with the 3D digital model of Mrs.Flaxman by the British artist John Flaxman, who used to be a professor at the UCL Slade School of Art. Copyright Mona Hess, UCL CEGE.

The creation of these 3D digital objects can be produced by ‘3D imaging’. We will be using “non-contact optical surface imaging”. The surface of the object will be recorded from all angles, and the model can be turned, zoomed and panned, almost as if you would have the real object in your hand.

For creating three dimensional images of printing plates, dies and rollers we will apply and combine different technologies:

  • Photogrammetry and ‘structure from motion’ is based on photography. We will produce a set of images while walking around the object. Usually the camera settings, background and lighting does not change while we do that. A software programme is then able to compute the common points to create a three-dimensional surface of the object with the colour, called ‘texture’. To be able to apply a scale to the object we need to include some known lengths in the photographs. This method is versatile with regards to object type imaged the equipment is very mobile, and the equipment affordable.
Photogrammetry of an Egyptian Cartonnage Mask from the UCL Petrie Museum of Archaeology.

Photogrammetry of an Egyptian Cartonnage Mask from the UCL Petrie Museum of Archaeology. Copyright Mona Hess, UCL CEGE.

An Egyptian is placed under the PTM/ RTI dome at UCL with 64 different light positions.

An Egyptian artefact is placed under the PTM/ RTI dome at UCL with 64 different light positions. Copyright Mona Hess, UCL CEGE.

  • Low cost 3D laser scanning can use sensors usually intended for gaming, like the Xbox Kinect. These sensors have inbuilt range sensing with human gesture recognition (natural user interfaces) that allow for objects to be captured using infrared signals. From initial tests we know that this technique is able to record the shiny surfaces of the printing plates. The information will give an overall picture, but not enough detailed information of the surface.
A low cost 3D sensor is used to 3D scan a Sepik Yam mask from the UCL Ethnographic Collection.

A low cost 3D sensor is used to 3D scan a Sepik Yam mask from the UCL Ethnographic Collection. Copyright Mona Hess, UCL CEGE.

  • Therefore we will also use High resolution 3D colour laser scanning on selected objects. The Arius 3D colour laser scanner is installed fixed in an air-conditioned room and used for high-quality digitisation of museum objects.  While this will give us a very detailed surface geometry, all objects will need to come to UCL.
The high-resolution 3D colour laser scanner at UCL is set up by Mona for the scanning of a relief of Mrs Flaxman by the British artist John Flaxman, who used to be a professor at the UCL Slade School of Art.

The high-resolution 3D colour laser scanner at UCL is set up by Mona for the scanning of a relief of Mrs Flaxman. Copyright Mona Hess, UCL CEGE.

As you might have gathered, the printing plates, dies and rollers will be difficult objects, so multiple techniques may be enlisted for each object. We will have to combine recording methods to find out how we can represent the fine engraving used in the dies and the overall geometry of the plates.

We would like to invite you at the end of the project to get your hands on the digital 3D models and tell us what you think about them. It is important for us to know how detailed these objects should be and depending on how you want to use them (i.e. on your mobile phone) the resolution can be lower.

If you are interested to know more about the technology, please visit Science of 3D where we explain the science behind our optical 3D imaging.

Stay in touch with me by following @Mona3Dimaging .

-Mona Hess, UCL

For the time being, we would love to hear your thoughts on this project. How would you use these 3D objects? Would you like to see them in an exhibition? We look forward to hearing what you have to say!

Stamp printing plates, dies and rollers: from vault to view

Over the next year, our Philatelic and Digital teams will be working with UCL’s Mona Hess, Research Associate and PhD candidate at UCL, to digitise objects from our collections, including printing dies, rollers and plates. These objects are difficult to photograph and not available for consultation by the public. This project, funded by Share Academy, will provide access to these important objects through a combination of a number of technologies. The final output will be set of 3D digital objects for use by philatelic enthusiasts, researchers and the general public. This blog will regularly update you on what is happening along the way.

Mona discusses various imaging techniques and engagement outputs for the 3D objects. A stamp plate sits at the centre of the table.

Mona discusses various imaging techniques and engagement outputs for the 3D objects. A stamp plate sits at the centre of the table.

Last Friday (24 January), we held a kick-off meeting for our Philatelic 3D digitisation project, a Share Academy project partnership with UCL. Because of the highly-reflective surfaces of these objects, a combination of technologies will be trialled to see which works best.  Some of the objects can be captured at the BPMA’s premises using techniques such as photogrammetry. Others, however, may need to be transported to UCL to be digitised with their large-format 3D scanning device.

Original Heath die of Penny Black with various other dies. (POST 118/1733)

Original Heath die of Penny Black (centre) with various other dies. (POST 118/1733). The reflective and finely-engraved surface makes them difficult to photograph.

Another highlight of the meeting was the demonstration of a possible output for the 3D objects: a mobile/tablet application. The Petrie Museum engages visitors using an application that explores the history of the Nile Valley with 3D digitised objects that can be manipulated by users.

Over the next month, our Philatelic team will be selecting various objects to be captured in the trials (due to take place from March), as well as planning any transportation of objects, where necessary, to UCL.

Are there any particular objects in the Philatelic collection that you want to see as 3D objects? 

-Rachel Kasbohm, Digital Media Manager