Tag Archives: digital techniques

A Day in the Life of…Alistair Branagh (Project Archaeologist, GIS and Survey)

My current role within the company is focused on GIS and survey. I am primarily based at our head office but from time to time I get released onto site to do some GPS or Total Station survey, or to provide some training in using our survey equipment to my colleagues in the field. Most of the time I can be found sitting at the computer doing GIS work.

Alistair fixing a camera — Some kind of electronics Frankenstein

What is GIS you may be thinking? GIS stands for Geographic Information System. It is a really important part of archaeology. At a basic level, it is essentially mapping. The GPS data taken on our sites to record the location of the archaeology we have found is brought to me. It is my job to firstly check the data for inconsistencies, format it appropriately and import it to the GIS. My job also involves digitising plan and section drawings and combining all of this information to create standardised figures for our reports.

It is a crucial role which allows me to be involved in many different projects and through every stage. As such I have a lot of varied tasks, ranging from georeferencing plans from clients and setting out trenches and site boundaries, to collating data at the end of a project. I’m also here to support staff in the field if they have a problem with the GPS or need an up to date plan of site. In a typical day I could be working on three or four different projects, completing any number of different tasks that are required. On occasion if a large project has recently completed, the GIS work may take up a large part of my week. It can be a time-consuming process and requires a lot of attention to detail to make sure everything is correct and accurate.

I spend some time looking after our survey equipment as well, checking that everything is working so that our field team have everything they need to do their job. From time to time I can also be found hunched over a dismantled camera like some kind of electronics Frankenstein, making sure they are cleaned and functional. On top of that, I often find myself being called on when my colleagues have problems with their computer!

It’s really difficult to try and paint a picture of a “typical” day in my job. It’s an interesting one because sometimes the days can feel very much the same but other weeks the days can vary quite a bit. It is for this very reason that I enjoy my job a lot as I never really know what the next day will bring or what new challenges will come along.

Our digital era

By Isobel Curwen (Heritage Research Team)

For centuries we have been leaving a written record of our daily lives and when we find evidence of this it is very exciting. Recent excavations in London uncovered a significant collection of Roman waxed writing tablets, some of the earliest hand-written documents found in Britain (for more information visit the MOLA website), and we have even earlier records such as prehistoric cave art and runic writing systems.

Our Finds team are currently analysing some stamped Roman pottery found in Lincolnshire. Mortaria and Samian ware are the most common pottery types to be stamped, although other types of Roman pottery were occasionally stamped too. The stamp could be a name or a word, or sometimes a symbol, possibly suggesting that the potter was illiterate (Read our blog post by Alice for some examples of stamped pottery found in Lincoln). In order to create the impression on the pot, the stamp had to be created in relief and in reverse which requires considerable skill (see how quickly you can spell your own name backwards!).

Stamped mortaria found from Lincoln - see the range of potters marks from symbols to words

Stamped Mortaria found from Lincoln – see the range of potters markings including both symbols and words

Roman grey ware pot base with a pot firing ‘X’ graffito that has been trimmed to form a disc or counter (Photo Credit Hugh Fiske/Ian Rowlandson)

These lovely sherds of stamped pottery have survived for thousands of years and this got us thinking. In today’s digital world what record will we leave of our own lives? Handwritten letters have been replaced by emails and text messages. Digital mapping and GPS render paper maps obsolete, used only when technology fails us or when there is a lack of signal. In our on-site recording of archaeological sites we use a combination of physical and digital recording techniques. With recent advances in archaeological practice suggesting and implementing systems for entirely paperless recording systems (Roosevelt et al. 2015) we are heading in the direction of an almost entirely digital historic record.

It looks like the record we leave about our lives will be less tangible and physical than that of our predecessors. Read the following article for more information on our digital footprints.

Christopher H. Roosevelt, Peter Cobb, Emanuel Moss, Brandon R. Olson &
Sinan Ünlüsoy (2015) Excavation is Destruction Digitization: Advances in Archaeological Practice,
Journal of Field Archaeology, 40:3, 325-346

Digital Past Conference Workshop

By Shoned Jones (Project Supervisor)

During this year’s Digital Past Conference in Aberystwyth, we were invited to attend and take part in a workshop discussing the management and archiving of digital datasets. A number of organisations were asked to attend the workshop and give short presentations on how they use digital data.

Along with Allen Archaeology the speakers were from; Archaeology Data Service, The Discovery Programme, DigVentures, Historic England, Wessex Archaeology and the University of Bradford.

Chris Casswell, the head of fieldwork at DigVentures and Li Sou, a PhD student from Bradford hosted the workshop.

While a number of topics, including storage space and metadata were covered, the one most affecting our sector was archiving. In commercial and field archaeology we are required by law to archive the data that we collect for clients as part of the planning process. If you are unfamiliar with this archiving method please follow the link here to our blog explaining archiving.

The main observation was of a blinkered understanding by research groups of the differing archiving requirements commercial units deal with on a daily basis. There is a lack of cohesion with regard to the physical archives and the proposed use of digital archiving with ADS.

Archiving requirements and field methodologies differ from county to county. Field methodologies are usually very similar with differences usually in the kind of cameras used and the specificity of the sampling method (how much we excavate and environmentally sample). However, archive requirements can differ greatly and with technology changing at such a rapid pace and companies working in all different parts of the country it is an issue that is becoming more and more important.

While in the past a small to medium archaeology companies may only work in one county and only deposit in one archive, the nature of commercial archaeology now enables companies to work all over the country. This is a wonderful opportunity for a company and for archaeologists to encounter all sorts of archaeology in their career without having to work the ‘archaeological circuit’ (working on temporary contracts from company to company). However, it does make the work of our post-excavation archiving teams difficult.

These differences are down to a number of reasons. Funding is foremost in this and it is not an easy fix. The issues that other groups brought in also include differences in storage requirements and having appropriate systems to store and process the metadata. These are also not easy fixes and require much collaboration between many different groups, including commercial archaeology units. This conference was one of the first to begin the conversation and in bringing together people from all sectors of archaeology I am optimistic that we will develop something that is more suited to both research groups and commercial companies.

3D image created by Shoned of a medieval ankle-boot found in Lincoln

P.S Some of the terms used in this blog are quite industry heavy, here for your perusal is a Glossary to give you a hand.

Archiving:

All of the information that we acquire on an archaeological site, context sheets, photographs, the final report and finds are all deposited within the local archive for the area of that site. In order for that data to be compatible with other data that other companies and research groups deposit, it must be submitted to conform with specific requirements which can be unique to each archive, .i.e. photograph formats (TIFF or JPEG), report formatted as pdf.

Digital vs Physical Archiving:

Physical archives are the finds themselves (pottery, animal bone etc) and the paper documents that were created on site, such as the context sheets, printed photographs (in the case of film photographs, slides and negatives), printed copies of the report and such.

Digital archiving are the photographs as digital media (JPEG, TIFF) archived using ADS (Archaeological Data Service), by uploading the files to a digital archive. This can include digital versions of the report, 3D models, GIS projects, CAD drawings, Geophysical data etc. I could go on and on.

Metadata: data that describes and gives information about other data e.g. a photograph that contains information regarding the date and time it was taken.

Digital Past Conference

By Shoned Jones, Project Supervisor

In February a colleague and I braved the trek into my homeland to deepest darkest Aberystwyth in Wales for a conference unlike any other in Europe, completely centred on digital archaeology and specifically 3D imaging and its use in Heritage.

The conference was held in the University, by the Royal Commission of Wales, presenting their flagship project, CHERISH. It was the 10^th anniversary of the conference and the keynote speakers were all heritage and field archaeology giants. We were invited by DigVentures, Head of Fieldwork and ex-Allen Project Officer Chris Casswell, and Bradford University PhD student Li Sou to participate in a workshop dedicated to the archiving of 3D and other digital data.

The conference itself was fascinating, especially to an innovative company like ourselves to see what’s happening on the other side of the archaeology spectrum (a.k.a research archaeology) and how developing technology is being used to further the study of groups such as English Heritage, Historical Scotland, National Trust and CADW.

From my perspective, having been entrenched in the commercial sector for the last few years and out of the research loop, seeing the development of this technology and how we aim to implement it further into our methodology was wonderful. While 3D imaging has been a mainstay when listing archaeological recording, its use and study for fieldwork has mainly been an addition (a pretty picture) for years. Its actual use as a replacement recording method was limited. However, times have certainly changed and now it appears to be a standard recording method, used either in conjunction with 3D laser imaging or as a stand alone recording method.

This is great news to companies like Allen Archaeology. Knowing that the research sector is using this method even more comprehensively than we previously thought indicated that we are on the right track. Conferring with other conference attendees about the more complete recording methods and the different outputs that can be created from this 3D model now presents us with new interpretation and recording possibilities.

In general, the conference was fascinating and informative, and we will be writing a secondary blog regarding the outcome of the workshop and a summary of the points raised.

If you would like to know more about our use of Structure from Motion or any 3D modelling please check out our youtube channel and the previous blog about Weston Park, Staffordshire, a Building Survey conducted with a mix of recording techniques.

Shoned Jones discussing her recent work using 3D imaging

https://www.allenarchaeology.co.uk/portfolio/weston-park-staffordshire/

http://www.youtube.com/channel/UCTqrx7nCdLBGM3U0oo6Q9sQ

Cathedrals and sandcastles at the Lincolnshire Show

Feenagh Johnson, Project Supervisor

Tucked among the various stalls at the Lincolnshire show 2017, Team Allen joined the wonderful people in the Cathedral Tent and the Lincoln Cathedral Connected project to perform a little bit of community outreach and to show off some of the cooler parts of our work!

Director, Mark Allen chats about the Cathedral excavations

Over the course of the Show, countless cups of coffee were consumed (thanks to Stokes) and even more people were introduced into the wonderful world of archaeology, engaging with our reconstruction pots; mosaic tiles and plans of our works at the cathedral and of course Pighill Archaeological Illustration’s virtual reconstruction of the Works Chantry, which quite literally brought the archaeology we had encountered to life!

Fee with a reconstructed pot

It was great to see how enthusiastic and interested the public were in their local heritage, but the centrepiece of this adventure was without a doubt the sandpit. Armed with trowels, little spades and of course finds trays and brushes, a small army of budding archaeologists (hopefully!) jumped at the chance to explore what it was like to be a real digger.

They travelled from Ancient Egypt, with a sphinx and a couple of pyramids; through the Roman Empire, with a fort and colosseum and then back home again with a castle and a very artistic representation of Lincoln cathedral, unearthing all sorts of artefacts (including what we were told were real dinosaur teeth!). At the end of the two days we can’t help but wonder…who had the most fun in the sandpit… the kids or the archaeologists!

Sand Cathedral

Nicky and Bill with their sand castle

Islamic Palaces 1 – The Alhambra Royal Workshops Project

Over the past 6 months I have been working with universities in the south of Spain to investigate workshops and production areas within medieval Islamic palaces. This, the first of two blogs, will focus on trips taken earlier this summer to the Alhambra in Granada.

Arabesque and tiles

For those of you unfamiliar with the site, the Alhambra is a large palace and fortress complex situated on a promontory at the foothills of the Sierra Nevada, overlooking Granada. It was constructed in the 13^th century AD during the Nasrid dynasty, a late Muslim dynasty in the south of Spain, and the palace is best known for its highly ornate arabesque reliefs, glazed tiles, pottery, glass and of course the beautiful gardens; and it was these gardens that had attracted the attention of academics from the Universities of Bournemouth, Newcastle and Granada. The question they were all asking – where exactly were the tiles, pottery and glass produced when the site was initially constructed?

The current gardens are a relatively modern addition and much reconstruction work of existing structures had been done to tidy its appearance; however, upon closer inspection some of these structures formed ‘keyhole’ shapes in plan, typical of kilns or furnaces.

Keyhole kiln

Prof Kate Welham and Dr Derek Pitman from Bournemouth University took the lead in May, undertaking a non-invasive survey of an area of garden using a whole suite of geophysical techniques (fluxgate gradiometer, electromagnetic survey, magnetic susceptibility and ground penetrating radar (GPR)), plus portable X-ray fluorescence (p-XRF). This approach was taken because of the likely nature of deposits beneath the surface – the site had been occupied by Napoleon’s forces during the Peninsular War, but upon his retreat significant parts of the fortress were destroyed including, most probably, the area of garden under survey. As little or no archaeological work had been carried out before, no one knew quite what to expect.

Surveying

Now, my first piece of archaeological fieldwork took place in 2000, and I’ve been in and out of the field ever since, but until this moment I’d never performed a geophysical survey. I’d always been that guy who can dig and, in more recent years, the GIS geek, often working with geophysical data but never collecting it. So just to prove to everyone that it did actually happen I got someone to capture the moment…

Using GPR at the Alhambra

I’m afraid I’m not able to reproduce the results in this blog, but I can say that several areas indicated the presence of high temperature activities. These results informed the implementation of an excavation strategy, and a couple of months later, two trenches were opened to investigate various magnetic enhancements recorded during the geophysical survey. These were directed by Dr Chloe Duckworth from Newcastle University and Dr Alberto Garcia Porras from University of Granada, and I was invited along to survey their findings and introduced them to the use of SfM to reconstruct a 3-dimensional image of each trench.

A trench being excavated

It was their first digging field season and the main priority was to take the topsoil off and map the uppermost deposits and any structural remains. Once this had been achieved it became increasingly apparent that the site was more complex than first thought. It had been occupied on and off for the past 800 years and many of the remains date to later activity, including the modern reconstructions which now mask the true nature of the kilns.

I hope to return in 2017 when these remains can be investigated fully and the full extent of production within the Alhambra is likely to reveal itself.

The Virtual St. Stephen’s Project

In Spring 2016 we were subcontracted by University of York to convert a visual model of the pre-1834 House of Commons, St. Stephen’s Chapel Westminster to an acoustic model. The work was commissioned as part of the Virtual St Stephen’s Project, an AHRC-funded research project and was a collaboration between the departments of History (Dr John Cooper), and Electronics (Dr Damian Murphy).

One of the major elements of the project was the creation of a three dimensional computer model detailing St. Stephen’s chapel at various points in its lifetime. The three dimensional model was then used on a touch screen device to allow visitors to interact with the reconstruction. Creating these models not only provides a great opportunity for public engagement it also allows evidence from a range of sources to be brought together and used to create an interpretation of a lost space.

The Virtual St Stephen’s Interactive model

However, as beautiful and engaging as these models are they do not consider the soundscape of the space. In recent years archaeologists have started to explore the opportunities for applying acoustic technology. Catriona came to AAL following the completion of her PhD looking at this technique.

For the Virtual St Stephen’s project we started with the three dimensional mode produced by Dr. Anthony Masinton and simplified it to use as an acoustic model. Acoustic technology is not as sophisticated as the technology to produce visualisations; the models have to be less complex. They also use the same information in slightly different ways. Both models require the size and shape of a space to be accurate, however; where a visualisation needs information about how surfaces are coloured and textured, an acoustic model needs to understand how sound will reflect, or be absorbed by different materials.

The acoustic model of St. Stephen’s Chapel, Westminster

The resulting model can provide a series of numerical values which tell us about the space; how sound decays from various positions in the room, how clearly sounds can be heard. We can also create auralizations; acoustic reconstructions. Under the right conditions they allow a listener to experience sound from the modelled space. We hope to use these models to explore the experience of listening to speeches in the pre-1834 House of Commons.

The project featured on The Lost Chapel of Westminster on BBC Parliament on Sunday and is still available on iPlayer.

Digital Techniques: Structure from Motion (SfM) Photogrammetry

Warning: Images of human remains feature in this post

If you’re involved in the heritage sector then chances are you’ve seen a three dimensional (3D) model of an archaeological site, feature or artefact that you can view and interact with on a computer screen or mobile device. It’s likely this was created using SfM, which operates under the basic principle that 3D structure can be resolved using overlapping images. Photogrammetry is the science of making measurements from photographs. Therefore, SfM photogrammetry is the use of photographs to accurately record 3D models from which measurements and details can be recorded. I could go into more detail regarding the technique itself works but for now lets just assume it’s tantamount to magic!

Capturing a collard urn

We’ve been exploring the possible uses here at AAL for a couple of years now after initially learning about its potential from the master of archaeological photography, Adam Stanford (http://www.aerial-cam.co.uk/). Initially we trialled the technique out in the field for the recording of skeletons and masonry because these are two often poorly recorded feature-types; that and our office at the time was somewhat unsuitable for artefact recording (to put it mildly) and my spare bedroom/dark room at home was full of kittens. What we found was that, if recorded properly on site, the technique allowed for a more accurate record of the feature from which a traditional illustration could be made and disseminated to specialists to aid in their assessment/analysis.

Example of a record using SfM on site

It also allowed us to revisit these features from the comfort of the office (the new one, not the old one) and examine them in closer detail than we had time for on site.

Masonry recording

By the time my fieldwork marathon was complete we had a new head office in Lincoln with plenty of space for us to experiment with SfM on artefacts. Trial and error was key here, and there were many failed attempts before finally working out a methodology fit for the task (credit must go to Hugh Fiske for providing the inspiration needed to complete this and I’m sure you’ll agree he’s made some beautiful models, http://www.archaeo3d.me.uk/)

Part of the company ethos here focusses on training for all, and as soon as we were happy with the workflow we began training others in this recoding technique. Currently we’re building up a portfolio of models so that in the near-future we can showcase them online for everyone to access, so watch this space.

Chris training Andrea and Charlotte in Structure from Motion

A postcard from Oslo

At the end of the March I spent four days at the University of Oslo for the Computer Applications and Quantitative Methods in Archaeology (CAA) annual conference. AAL were fantastic and supported my attendance, as did a low income bursary from CAA International. Last summer, prior to getting a job with AAL, I agreed to run a session with Stuart Eve of LP Archaeology at the conference focussing on digital approaches to multisensory engagements with the past (Interpretations from digital sensations). We decided to run the session on the back of a series of discussions we have both had on twitter about each of our research trying to move beyond a visual interpretation of the past.

Piotr Dziewanowski from the National Maritime Museum in Gdańsk presenting scans of the Soldek

Lawrence Shaw’s 3D printed Digital Elevation Model

I presented a paper in the session and we had two other speakers; Lawrence Shaw of the New Forest National Park and Piotr Dziewanowski from the National Maritime Museum in Gdańsk. My paper seemed to go down fairly well, which is always nice, and the other two papers were fantastic. The team from Gdańsk presented a series of scans of the museum ship the Soldek, which looked like an incredibly complicated project and produced some amazing outputs. While Lawrence Shaw and his team demonstrated the use of 3d printing to engage the public with the Lidar; letting people “get tactile” with the landscape.

While I was out there I also had some great conversations about how to introduce more digital techniques or applications into commercial archaeology, a slightly ignored subject, and “enthusiastically” discussed over a few glasses of wine at the fantastic Museum of Cultural History… The underlying theme of those discussions was not that commercial archaeology did not need to introduce new and shiny methodologies and applications, but rather that there was no time in the commercial world to roll out and field test new on site approaches and in the UK archives are frequently not willing to accept digital data. For example, I saw numerous approaches to using tablets onsite for recording, instead of the traditional context sheets. This would allow us to avoid digitizing these at the end of the project and should in theory force the appropriate data to be collected in the field. However, setting up and ensuring this system works on the software end would require a lot of development. There are costs associated with buying in the kit. And also is the hardware capable of dealing with a British winter… (Though Mike and Flo from LP highlighted that you can buy ruggedized tablets; the issue is ensuring they are cleaned and dried on return from the field).

One of the Viking Ships and the incredible building they are housed in

Detail of the woodworking from one of the ships

Somewhere along the line we went to visit the Viking Ship Museum, where my inner maritime archaeologist got very excited. The boats, the artefacts, the preservation, and the building they are presented in is amazing!

One of the sessions that really stood out for me was run by Gary Lock, Agiatis Benardou, Costis Dallas, Paul Reilly and Jeremy Huggett; a roundtable on scenarios for the next five years of archaeological computing. It was a really challenging session making us all think about the future of digital archaeology and I’m looking forward to hearing about the follow up to the session.

Finally on the last day I “conference-bombed” the digiTAG session ran by my friend Sara and her colleagues. They had a couple of presenters drop out and wanted to fill a couple of spots. All I can say what seemed like a good idea at 10pm after a few pints seemed less appealing at 6am the next morning. But I gave a quick presentation on theorising archaeo-acoustics, a presentation I had wimped out of submitting to their session in the first place; and I think it was well received (or at least twitter seemed to think so). The whole session was fantastic and drew together a number of my thoughts on the lack of theoretical engagement with digital approaches. I was sad to miss the concluding discussions.