That photogrammetry, the method of calculating 3D representations from a series of 2D photos, can be a great tool in palaeontology is quite obvious when you take a look at Peter Falkingham’s paper in PE (and the many other papers on the method out there). But just how good is it? I’ve previously shown results from a free service on the net, and from my own photo tour of the Stan T. rex skeleton in Brussels. Today, I want to show you sometimes, things can go so wonderfully right that there simply is no better way to digitize a bone than photogrammetry.
As you can see, I was able to have it pulled into the center of a large space, so that I was able to take 111 photos (yes, that many!). I made sure to get shots in circles, moving horizontally about 10° between them, one circle from just above the ground, one from shoulder height, and one standing on top of a table that I dragged around the bone. Additionally, I took some shots from closer in, trying to capture the down-facing parts of the glenoid and so on. A handful of photos were slightly out of focus, so I deleted them.
And this is what agisoft Photoscan and about 30 minutes of editing spit out (vertex color removed, to make the quality of the surface better visible):
Oh, I should note that this is 10% of the original file size, too 🙂 There were a few holes to close, but very few issues with sharp changes in geometry. Thus, the editing was very easy. I wish all my attempts had worked out so well. Check out what became of my attempt to use photos of the mounted Giraffatitan to get a 3D model of the humerus:
And yes, the lower side is fine, but this side is concave instead of convex (under all that rubble).