Deep B.V. from Amsterdam is a specialized hydrographic surveying company with close links to Skeye. Deep carried out measurements under water near a breakwater by using a multi beam echo sounder. To measure the part above water level there were two options. The first was to let land surveyors climb over the jagged edged blocks or to use Skeye’s unmanned helicopter. It was decided to go for the last option. The reasons for this were the fact that climbing the rocks would take a lot of time and is extremely dangerous. Land survey is also next to impossible as an enormous amount of points need to be measured to create a realistic 3D model. In order to gather extra sharp imagery and high accuracy in the measurements the flights were conducted at a mere 40 meters above the breakwater. In addition ground control points were measured using RTK GPS so that the 3D model would have the right coordinates.