Photogrammetry

 

Photogrammetry is an incredibly powerful tool that turns cameras into 3D mapping and object recording devices. Only recently has the software, computing, and camera technology aligned to make this a fast, easily applied technology and the possibilities are boundless.

My first experiment with photogrammetry was reconstructing a 3D model of a 211 million year old fossilized tree in the Black forest part of Petrified Forest National Park. This was part of a project to identify the first fossilized fire scar for a scientific study recently published in Paleo 3 (Paleogeography, Paleoclimatology, Paleoecology) titled “First known fire scar on a fossil tree trunk provides evidence of Late Triassic wildfire“.

The process involves taking photos of an object from different angles – this can be from the ground or from the air.  The software then finds matching points on the different images and calculates the angles of each photo to create a 3D point cloud of the surface of the object.  Not only does this provide a 3D rendering of the object, it also retains the visual appearance of the object as well.

3D Point Cloud of petrified log

Pix4D rendering of the camera angles for the Petrified Forest log

In this case we can see the 74 images that were used to develop the point cloud and their positions in space.  The software then fills in the surfaces from the photos take to reveal the incredible detail and complexity of the surface.  This allows researchers to see the exact same thing that we saw in the field and better understand the context for the samples that were taken.

Full color photogrammetry rendering of petrified log

The petrified forest log in all it’s glory as it sat, and still sits in the Black Forest sector of Petrified Forest National Park

 

I am currently working on aerial photogrammetry and look forward to figuring out how to apply this tool to climate and glacier research.  Looking forward to posting more tests soon.