I’m Martin Devereux, Head of Digital at The Postal Museum. We opened in London last summer (2017). Our aim is to showcase our stories and collections and reveal the fascinating story of Britain’s postal heritage in an engaging, interactive, educational, and fun way.
I’m an archivist by training. I was originally employed to catalogue material in the Royal Mail Archive, which contains material documenting the history of the postal service in the United Kingdom. One of my responsibilities was to catalogue and digitise the photographic library which has glass plates, albums and film, so I had to learn about digitisation techniques and processes.
Digitisation at The Postal Museum
Back in 2012-2013, we were thinking about audiences for the new museum. We talked lots about the areas of our collection that are largely inaccessible to our audiences and, in particular, how difficult it was to show the artefacts we had from the stamp printing process. We have lots of dies, rollers and printing plates which have been used on some very iconic stamp issues. These are mostly made of metal, with glossy surfaces. These are 3D objects and we felt that, although straight photography can help audiences envisage them, it would be better to try and find new ways to show their physical properties.
In 2013, a visit from the Digital Humanities team at University College London (UCL) put us in contact with Mona Hess, then a doctoral student working in UCL’s Civil, Environmental, and Geomatic Engineering Department. Together we submitted a proposal to Share Academy – the London Museums Group’s partnership with UCL and University of the Arts London (UAL) to encourage museums and academics to work together. We wanted to test 3D techniques on the philatelic printing material (and other selected objects from the collection). Our bid was successful and the funds paid for Mona to undertake the tests and teach us a few tricks! The money also paid for photogrammetry software and some 3D prints. You can read about the project on our old blog.
While this venture with (now Dr) Mona Hess was taking place, my colleague, Rachel started a conversation with the team at ScanLAB Projects, whom she knew from her days as a Digital Humanities student at UCL. The museum had recently reached agreement with Royal Mail to take part of its disused underground railway network (known as Mail Rail) and turn it into a visitor attraction. We were concerned with documenting its physical state before we moved in and changed it. We’d seen ScanLAB’s work at The Science Museum’s shipping galleries and thought it a good way forward. A bit of salesmanship on my part convinced our Directors to let us do the work and ScanLAB did the surveying in December 2014. Now, three years later, visitors are riding trains in the old Mail Rail network and ScanLAB have made two interactives to show visitors how the old depot and platforms looked when they were abandoned. You can see some of the visualisations here.
Why 3D?
Aside from the interactives we have done with ScanLAB, we’re now creating more accomplished models using the photogrammetry techniques we started learning with Mona.
Our reason for carrying on producing 3D content is that it’s so useful! We can use them as part of our documentation process for objects, and the accessibility they can provide for artefacts that are usually only seen behind glass is exciting. We have ambitions to create more models for 3D replicas to aid handling sessions and sensory experiences in our outreach programmes.
One of my colleagues, Hannah, is prototyping a VR online game to go with our current temporary exhibition, Voices from the Deep, which is about mail recovered from a sunken vessel. In the game, players can descend to the seabed and collect objects from the wreck. Hannah is using the 3D models we’ve created to populate the game. The game’s aim is to use technology to enhance the user experience by allowing participants of all ages and abilities to link visual clues to produce an exciting all round experience. This teapot is one of the models made using photogrammetry.
Workflow and Equipment
Photogrammetry is the technique we employ. We tend to use our Canon 5DSR for the capture, though sometimes we do deploy our Phase One XF with 100 megapixel sensor and see what we get. Generally we use a slightly wide-angle lens and a very small aperture to achieve a large enough depth of field to capture the whole object in focus. The camera is set up on our motorised FOBA studio stand and the subject placed on a turntable. We have a manual turntable at the moment, with degrees marked carefully to aid turning.
We use studio flash lighting with large softboxes placed at 45 degrees to the subject to create flat and even illumination and a contrasting neutral paper backdrop (darker paper for light-coloured objects and lighter paper for darker-coloured objects) to aid background removal. We create custom colour profiles for each of our cameras to assure our colour and tonal capture is as accurate as possible. We try to capture 3-6 circles of images from various angles and then put them through Agisoft Photoscan to produce the models. Andrew Bruce, our Digitisation Officer, is a prodigiously talented photographer and has perfected the lighting and workflow process. He’s really brought our photogrammetry to new heights.
Challenges
Time is always the biggest challenge for us. We’re a busy organisation and our digitisation team is always busy doing work for the museum, or for external clients. We try to programme in chunks of time to carry out the capture work and then fit the processing in around other commitments.
Thinking about getting into 3D?
Just start. To begin with, you don’t need lots of expensive equipment and the results can be very good. Don’t be too daunted by the learning curve – you can do it and there’s lots of people out there who you can seek out to gain advice and tips.
If you can, enlist help. In 2015 and 2016 we had two students on UCL’s Digital Humanities undertake placements with the team. Both Rose Attu and Whitney Christopher experimented with photogrammetry – testing objects, testing equipment and seeing what results they could get. This helped us a lot in determining the viability of continuing our 3D activities.
The future of museums and 3D
3D objects will get easier to produce – I do think that cultural organisations will increasingly use 3D visualisations to document their holdings as part of their collections management process, as much as for reasons of accessibility. Yes, the cultural sector needs a better understanding of how 3D models ‘represent’ the real physical counterparts and the debates over the accuracy and authenticity of modelling processes need to continue, but the opportunities for engagement with audiences shouldn’t be overlooked.
Our favorite historical piece on Sketchfab
https://skfb.ly/T8nD
I love this helmet from The Royal Armoury in Sweden. When we saw this, we realised that it was entirely possible to achieve decent photogrammetry results with shiny, metallic objects.
Sketchfab / Twitter: @thepostalmuseum , @martydev, @andrewpbruce, @hannahwinn3 / Website
About the author
The Postal Museum
Photogrammetry from The Postal Museum Digitisation Studio
