My name is Jacob Kordeleski, and I am an undergraduate student working in the collections of the Cleveland Museum of Natural History. Currently, I am entering my junior year as a Classics and Anthropology major at Case Western Reserve University, a neighboring school which often cooperates with the CMNH.
While I am a student of Classics at Case Western, I have also been a work-study employee for the Department of Invertebrate Paleontology at the CMNH since enrolling in college.
I could not have been able to do the work I have without the shared knowledge of others. I first became aware of the uses of 3D modelling for cultural heritage at the Corinthian excavations at the American School of Classical Studies in Athens. A member of the excavation team used drone photos to stitch together a 3D mesh of the entire dig site. I knew that the same technique, photogrammetry, must be able to be applied to smaller objects, such as those in museum collections. Searching the web led me to Sketchfab and the work of Dr. Heinrich Mallison, who authored a paper with fellow paleontologist Dr. Oliver Wings, titled “Photogrammetry in Paleontology – A Practical Guide.” Learning from him and the countless other creators on Sketchfab and other internet communities, I began experimenting with the use of photogrammetry to create 3D models of specimens in the Invertebrate Paleontology collection.
3D at the CMNH
As is true for all museums, the vast majority of the CMNH collection lies in a maze of cabinets, boxes, and shelves far away from the eyes of any average visitor. While professional researchers may visit these off-exhibit collections, they may often need to travel hundreds of miles to see specimens which might not even end up significantly contributing to their work. As a result, a huge repository of scientific knowledge and wonders is effectively invisible to the public. An employee in the Department of Invertebrate Paleontology, I need only look into our Typed and Figured Cabinet (the designation for specimens important enough to be cited in papers or named a new species) to find amazing fossils which have never been exhibited. I am currently in the process of creating 3D models for our Typed and Figured specimens which function best in the 3D format.
Because creating 3D models is a time-intensive process, fossils which can most benefit from being viewed in three dimensions are digitized first. For example, while a simple mollusk (think of a clamshell) presents itself no differently in 3D than in a glass museum case, many specimens, such as our recently uploaded Rusophycus, actually offer a perspective in 3D greater than in a traditional museum setting.
This Rusophycus specimen is part of an ongoing research project of the Department of Invertebrate Paleontology at the CMNH
This Rusophycus is an ichnofossil, or trace fossil, meaning that it displays evidence for movement and existence of an animal and not the actual thing, similar to a footprint. While an untrained eye might assume that the grooved protrusion on the top of this slab is the preserved cast of an ancient animal, an experienced fossil hunter will see that this protrusion should actually be viewed as the bottom! Some animal, similar in shape to a horseshoe crab, burrowed into a plane of sand. Other sediment filled the groove, solidifying into the protrusion we see today. Looking at the cross-cut of this slab reveals another trace fossil on the side in an inverse orientation. Mounted in a glass display case, this fossil might only confuse a viewer or require a large amount of written explanation. The 3D format, however, allows viewers to rotate the slab 360° and methodically deduce the proper orientation of the fossil, just as if he or she were a real paleontologist in the field. It is specimens such as this Rusophycus which truly demonstrate the full capabilities of 3D for museum collections and exhibits.
Workflow and Equipment
I use Agisoft Photoscan, photogrammetry software, to create 3D models of objects in the CMNH collection. For each project, I typically take 48 photos each from an upper angle and a lower angle before flipping the object and doing the same for a total of 192 photos. Depending on how visible the top of an object is, I may utilize one or more higher angles. While no exact count is necessary, I think many people agree that at least one photo every 10° is required to produce a high-quality, 3D reconstruction. For the photos themselves, I use the 18-megapixel Canon EOS Rebel T2i 550D. To fully optimize the conditions for up-close, well-lit photos, I utilize an all-white LED photo tent. I also place my objects on a turntable to maximize accuracy and ease of photo-taking.
I frequently tinker with the exact workflow. Ideally, I try to merge all photos into one chunk before generating a model. In these cases I use an all-white background and mask out any points the software might recognize. Some objects, however, are simply easier to compile into two or more chunks before aligning both into a complete and final model. In those cases, I’ll use a circle of cardboard with two different faces of newspaper. The different sides act as different backgrounds for the software to recognize, yet the attachment of the newspaper to a circular board allows me to place it within my optimized photo-tent. Also, I often employ acrylic cubes as object support. These are great for preventing shadows beneath the artifact or specimen as the software will not recognize any points within the clear plastic. I created the cubes myself using a laser-cutter, so I was able to construct multiple sizes and shapes to accommodate a variety of objects.
Challenges
While the trickiest part of pinning down a workflow for creating a model was simply understanding the conditions of the software, it was also very difficult to get this project started alone. I do not work with a skilled team of technicians, using a vast array of advanced equipment, or on a strict timeline. I, as I assume most creators on Sketchfab do, simply attempt to do the best I can with limited supplies and a great passion for sharing knowledge with the community. With professional and massive institutions such as the French national museum, which I greatly respect for its commitment to sharing its collections with the world, it can be very intimidating to begin the complex process of using 3D imaging in cultural heritage.
Oftentimes, however, the greatest projects begin with a small, individual effort. This is precisely why I began working with 3D for my institution. I believe that the seemingly minor contributions I make now will lay the groundwork for future cultural heritage projects, both at the CMNH and otherwise. If every cultural institution worked to share their fantastic collections digitally, we could make art, science, and history accessible to so many more people around the world. So the biggest challenge I have faced may have been simply staying determined with the project. Once I finally was able to put together my first impressive model, however, I was filled with a great drive to see how much better I could do.
Advice for Beginners
Look online! There are loads of guides and tutorials ranging from simple to comprehensive. I personally started because I saw the amazing work an archaeologist could do in the field with a drone scanner. From there, I immediately searched the internet and was overwhelmed by the amount of help I could find. Also, start small! Before you try perfectly recreating the 30-foot-tall tyrannosaur you have lying around, try creating something small and simple, just to learn the technique. Before really diving into a large model, I try to do a couple of small, lower-quality tests just to toy with the specifics of the object I am working on. Over time, I find myself wasting less and less time as I become more accustomed to the technique of photogrammetry. If anything is true about working with 3D, it’s that the more you do it – the better you become.
Moving Forward
I strongly believe that 3D is more than an eye-pleasing novelty for museum collections. Some of the most famous museums operating on Sketchfab – the French national museum, the British Museum – have made parts of their world-renowned collections available to people like me, who could very well likely never have a chance to visit them personally. With VR technology becoming more accessible every day, I believe we are even capable of creating customizable, digital museums. Educators could place the most defining fossils, artifacts, or artworks in a single, virtual room and use them to teach students using VR immersion.
A Favorite Historical Model on Sketchfab
One of my favorite models on Sketchfab relating to cultural heritage is that of the Segovia Cathedral, made by Nestor F. Marques. If you have seen pictures of Gothic church vaults, you understand that no 2D photo can do justice to the sheer amount of space and air medieval churches controlled. In a 3D format, it becomes possible to feel the space inside the massive cathedrals.
About the author
Cleveland Museum of Natural History
Scanning select specimens from the Cleveland Museum of Natural History collections and research division.
