Yes, looks like ground control points for photogrammetry. https://www.pix4d.com/...

		kbutler 3 months ago \| parent \| context \| favorite \| on: Titanic's sister, Britannic, sank in 1916. Divers ... Yes, looks like ground control points for photogrammetry. https://www.pix4d.com/blog/diving-into-underwater-photogramm...