TeramoMusiva: Creating 3D Models of Archaeological Finds to Highlight Heritage

About Me

My name is Rocco and I completed my cycle of humanistic studies at the University of Chieti with a degree in Post Classical Archeology, with a thesis on digital photography in archeology.

I have been working as a professional photographer since 1995; I specialize in still life photography of cultural heritage and archaeological finds.

I have collaborated with the university chairs of classical and medieval archeology of the University of Chieti, with the Archaeological Superintendency of Abruzzo, with the journal Archeo, and with the Museo delle Genti d’Abruzzo in Pescara.

In parallel with my photographic activity I have been active in the publishing and graphic arts sector, I have worked with various advertising agencies and printing houses, up to being first consultant and then technical coordinator of pre-press, offset printing, and setting up of the press and home center publisher of La Sapienza University of Rome.

My professional life has led me to be interested in different areas of communication, from offset printing to photography, web design, and videomaking. I started taking pictures with film and I learned how to accurately manage lights and framing. 3D scanning with photogrammetry was only one of the many new applications that digital photography allows. Here I will talk about the projects in which I am involved and how I carry out photogrammetry.

TeramoMusiva

I created the TeramoMusiva project, a multimedia archaeological tour dedicated to the ancient mosaics of Teramo city. The purpose of the project, born during the training of the regional course “Talenti per l’Archeologia”, is the creation of a widespread museum in the historic center of the city of Teramo. This museum, publicized through a web portal dedicated to it and on the social network Facebook, is intended to help increase the flow of tourists through the city.

The numerous archaeological sites in the historic center, rich in valuable paved remains, could be exploited by creating a tour dedicated to the mosaics. In addition to allowing visitors to admire fine examples of Roman mosaic art, such a tour allows them to understand how the residential district of Interamnia was structured between the late Republican period and the Imperial age.

The 3D models created for the TeramoMusiva project have been so appreciated that the DISPUTER, department of the University of Chieti has decided to incorporate it into the wider EuroTech project. Thus the web portal is used in the news section also to publish some experimental materials such as virtual tours and virtual museums.

EuroTech Project

I am, along with University G. d’Annunzio Chieti, the EuroTech Project grant holder.

The EuroTech Project concerns the creation of an innovative EU curriculum for a professional and specialist figure of ‘Archaeologist-Technologist,’ who can deal with diagnostic mapping, research, valorization, and publishing for the safeguarding of Cultural Heritage at risk, specifically archaeological heritage.

The project is developed along four axes: learning technologies, collaboration, mobility, dissemination/publishing of the results for a wider valorization.

The project, therefore, intends to promote an innovative EU curricular reform specifically planned for Archaeologist-Technologists, as well as figures interested in publishing archaeological subjects, and for technicians and archaeologists interested in projects of ‘sustainable valorization of archaeological sites’.

My specific scholarship in the EuroTech project is focused on 3D technologies for cultural heritage, and my goal is to develop and teach low-cost technologies for the dissemination of archaeological data. My scientific manager of the project is prof. Oliva Menozzi, professor of classical archeology.

My activity in the project also consists of taking photographs for remote sensing and for publications, paginating books, creating virtual photo tours, and creating websites with WordPress platforms on which to publish the realized contents.

But the activity of creating 3D models with photogrammetry and the creation of virtual museums is the one that engages me the most and gives me the most satisfaction.

The digital technologies that we develop and teach must be accessible in terms of both cost and time investment.

Digital technologies and photogrammetry are the two most successful techniques we have used to enhance small finds and ancient coins.

3D Scanning of Coins and Small Finds

Photogrammetry is an excellent tool for archeology. The realization of 3D models with the photogrammetric technique is affordable for archaeological teams because it does not require very expensive equipment and can be learned quickly. However, 3D scanning of ancient coins and small archaeological finds is more complicated and can give disappointing results if not performed properly.

My specialization in the EuroTech project is not only to scan small artifacts and coins but also architectural structures, large statues, archeological sites and other subjects. But I wanted to share a more unique experience by giving operative advice to colleagues who may have my same problems and maybe try to find a way to solve them. I want to share my experience to help archaeologists who are not technicians but want to use photogrammetry to scan small finds and coins.

Scanning coins in 3D can also put laser scanners in difficulty, but with photogrammetry you can get excellent results.

Digital photogrammetry allows us to easily obtain models that have a good mesh—although not always precise and detailed—and an excellent texture.

Taking Photos

Small objects, especially coins, need to be illuminated with a homogeneous and diffused light. Reflective materials also need to have a lit environment to reflect around them, otherwise they will seem dark. The light tent is the ideal solution to easily obtain a light cage.

For small finds, it is enough to illuminate by placing two lights on the slightly frontal sides.

For the coins, four lights are instead aimed at the corners of the tent.

For taking pictures, I use a DSLR Nikon D3X or D810 with a 105mm macro lens. I recommend using machines with high-resolution sensors and macro lenses with a focal length of at least 90mm, with a reproduction ratio of at least 1:4 to refine coins and very small objects.

The coin or archaeological find is placed on an automatic turntable. I use the Foldio360, which is controlled by the tablet or smartphone. I set an automatic rotation of 9 degrees and make at least two chunks of 40 shots with different views.

To take pictures of small ceramic vases, only two lights on either side of the lightbox are sufficient. To get the perfectly white background you will need to mask the images in Photoshop.

I take all the photos in raw format and process them in Lightroom. Usually I don’t make major adjustments, I just check the color balance, exposure, contrast, and texture sharpness. At the end I export the processed photos in jpeg format to build the 3D model.

Macro Focusing

The problem of close-up photography is the shallow depth of field that occurs at high reproduction factors. To increase the depth of field we have kept the reproduction factor low by taking advantage of the great resolution of the sensor that allowed us to crop without losing details.

However, to obtain perfectly focused photos, I use the focus stacking technique, which consists of taking more photos with different focus, which are then be combined with the Helicon Focus software into a single photo, taking only the sharp parts of each photo.

Photogrammetry Software

I have successfully tried many photogrammetry softwares and in the end, my choice fell on Metashape and 3DF Zephyr, both in the basic version. Occasionally in universities I use Metashape Pro when I need to enter metric references and markers.

Zephyr for the reconstruction of small objects and coins photographed in the studio on the turntable is more powerful and simple to use.

Metashape is preferable for situations in which the photos are not taken in ideal situations and it is necessary to work more in post-production.

Masking

For the scanning of small objects on the turntable it is very important to correctly mask the images. The masking step is one of the hardest parts of model reconstruction, because masking the photos is quite repetitive and takes a lot of time. But for a good 3D model reconstruction we need to create masks that isolate the subject from the rest of the image.

3DF Zephyr software provides a plugin, Masquerade, which is very effective and intuitive. But in Metashape, before using the mask tools it is better to prepare the photos in Photoshop to detach the image from the background.

The ideal would be to create tiff files with a mask in the alpha channel which can then be imported directly into Metashape. However with a little patience the selections can be done accurately in both softwares with the manual mask drawing tools.

Advice and Tips for Photogrammetry

In order to create excellent 3D models even with photogrammetry software without any post-production of the mesh and texture in other 3D softwares, you need to take excellent sharp photos and perform excellent image masking.

In particular, we need to shoot photos:

• in controlled light conditions, with uniform illumination, and without dark shadows;
• using a background of a different color from the subject;
• with perfect focus and sharpness;
• with the correct exposure;
• in raw format

Challenges

Italy is one of the richest countries in archaeological heritage but unfortunately it is perhaps the country where it is more difficult for archaeologists and specialists to earn a living from their work. There is much talk about the enhancement of cultural heritage but few projects are carried out and above all very little is spent on remunerating the staff. I hope that the spread of modern digital technologies that lower equipment-based operating costs may finally allow for investing in archaeologists’ salaries.

Technologies alone do not produce valid content. Only an archaeologist is able to produce content to enhance the archaeological heritage. So I think that archaeologists must learn to use modern digital technologies for the dissemination of archaeological data.

Conclusion

The 3D models published on the Sketchfab platform are very useful for the dissemination of archaeological data. 3D scanning provides a big opportunity to communicate and show people things from their own history and make them interested in viewing more. In fact, 3D models can encourage the public to go to the real museums.

Sketchfab is an excellent aid for archaeological research; scientists can explore models from all around the world without needing huge travelling budgets. This approach also guarantees complete safety for the original objects and is a great way to enhance archaeological heritage.

Digital photogrammetry and the Sketchfab platform are technologies with accessible costs. I hope they spread more and more in the world of archeology. I will work for this purpose.

Rocco’s Website / TeramoMusiva / Rocco on Facebook / EuroTech