For The Wrecks They Are A-Changin

The seabed and wrecks are dynamic environments. As divers we are not always aware of just how much things change unless something dramatic occurs. In 2012 the stern of the Karlsruhe was very ship-shape with neat lengths of teak decking in place. Then the stern winch capstan collapsed to the seabed and upended everything. Anything Read more about For The Wrecks They Are A-Changin[…]

Mesh it up – Depth Maps vs Dense Cloud

With the release of Metashape 1.5 we get a choice with the route to mesh creation: Depth Maps Dense Cloud For some purposes we don’t really need a mesh, the dense cloud is just a series of defined points in 3D space but can have GIS information and scale applied. But for most uses – Read more about Mesh it up – Depth Maps vs Dense Cloud[…]

Project Thistlegorm – The Processing Begins

The Project The SS Thistlegorm is rated a world class wreck dive. But only a tiny fraction of the world can don SCUBA and pay the wreck a visit, so the Universities of Nottingham, Ain Shams and Alexandria have collaborated to digitally record the heritage beneath the waves. Funding for this work has been provided by Read more about Project Thistlegorm – The Processing Begins[…]

The Art of DEM

The Art of DEM For some reason, I am drawn to Digital Elevation Models (DEM). They express so much information in such an elegant way. Their creation does require embedding GPS data, but thats almost a given these days as its a straightforward exercise pulling points out of sonar. In simple terms, a DEM is Read more about The Art of DEM[…]

Changing Wrecks – Which Version?

Things Change Shipwrecks are not static, unchanging places. As age, tide and corrosion take their toll things settle into the seabed. Prior to photography, and more recently photogrammetry, the changes would go unrecorded. But as those of us who dive the SMS Karlsruhe regularly, it is no longer possible to recreate this image as shot Read more about Changing Wrecks – Which Version?[…]

Mixing Datasets – Photogrammetry and Multibeam

The one nagging thought while scanning is “Did I get enough overlap?”. No overlap of points and the scan data just won’t build into a single, seamless model. For anyone scanning topside data the opportunity to reshoot the missing images can be straightforward, but with shipwrecks its not so easy. The distances involved, boat availability Read more about Mixing Datasets – Photogrammetry and Multibeam[…]