Return to Depth
Short discussion on first dive after COVID-19 lockdown and using UWIS tracker for 3D reconstruction and improving local accuracy of model with adjustments to tracker unit location.
Tag: DEM
DEMS – Another View
Slope Analysis As we have discussed before Digital Elevation Models help us understand subtle changes in depth (or height) of the subject. We also think they are art in their own right. Tucked away in the 1.4 release of Agisoft Photoscan Pro is a preference that adds slope analysis. The colours applied to the model Read more about DEMS – Another View[…]
Gone But Not Forgotten.
Maritime history preserved using photogrammetry as the remains of a torpedo inadvertently snagged by a tanker anchor in weymouth bay.
Bolt in the Bay – P47-D Crash Site
Background A few years back Grahame Knott of Deeper Dorset found the dispersed remains of an aircraft in Weymouth Bay. Over the years pieces of the jigsaw have come together, with pieces of information as diverse as component part numbers and an entry in the Portland War Diary (Held at the National Archives) all adding up to Read more about Bolt in the Bay – P47-D Crash Site[…]
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[…]
Geo Referencing the UB 116
Earlier this week Kevin Heath of Sula Diving kindly towed his side scan sonar fish past the remains of the UB 116, generating a very clear image of the wreck site: Relating the Model to the Planet With the GPS positions recorded in the sonar we can now extract a few key points and add them to Read more about Geo Referencing the UB 116[…]
Digital Elevation Models Revisited
The Model Digital Elevation Models (DEM) are one of the outputs photogrammetry delivers. They are (almost) free, as long as you have GPS data (Latitude, longitude and depth) for known points then orientating and generating a view of the undulations of the scan is straightforward. The SS Gwladmena was scanned back in August 2016. At Read more about Digital Elevation Models Revisited[…]
Digital Elevation Models
Next year sees the start of a little project run by The Shipwreck Project to find the missing pieces in a great story involving a Second World War single seat fighter that crashed in Weymouth Bay. We know the date and the fate of the pilot – he bailed out and was rescued – but we do Read more about Digital Elevation Models[…]