Turntable Photogrammetry

(Originally published 3/29/2021)

My initial attempts at photogrammetry used the walk-around method with mixed results. Still I kept at it, because the consensus on the web seemed to be that photogrammetry done with the turntable method–i.e., using images taken from a fixed location with an object rotating on a turntable–could be effective but challenging. The main reason seemed to be that the photogrammetric software performed best when background “clutter” was present, because it would help use that background clutter to help orient the photographs of your main subject. Photogrammetry using a turntable, on the other hand, was supposedly more effective with an entirely featureless background. (I have since heard and seen this refuted–and by now have my own examples where both are true.)

The consensus on the web seemed to be that photogrammetry done with the turntable method could be effective but challenging.

Nonetheless, while managing the many logistical challenges of the walk-around method, I yearned for an option that offered more precision. That was when I came across this post by 3D Scan Expert, in which the author, Nick Lievendag, discusses his attempt at making a 3D model using the Foldio360 automated turntable and app. He goes step-by-step (skipping some of the more tedious steps) through the process of creating a model using this turntable, which was initially created with product photography in mind. Lievendag’s review was fairly glowing with only a few reservations noted–notably about the cap on the resolution of the images taken using an iPhone (1000 x 1000). The attractive part was, of course, that you could do all of this ON an iPhone. Not to mention that the app was also compatible with DSLRs (with IR). So I took the plunge and decided to try out the turntable myself.

This seashell was the first model I made using this method. I used three sets of 48 images taken from three different perspectives (read: heights) and processed the model in Meshroom. I was pleasantly surprised to learn that for a mere $2.99 I could upgrade my Foldio360 app to the “Pro” version, which allows me to take higher resolution images (3000 x 3000–not perfect, but a marked improvement). I was also pleasantly surprised with the resulting model, which I was able to clean up quickly in Blender by removing a small amount of white “noise” around the base.

Ta-da!