Station installation

The actual installation consists of four phases:

1. Realizing the physical infrastructure for the system, often done by a contractor. This includes frames, towers, etc. on which to mount the camera, wiring between between cameras and computer if more than 10 m, the power supply, and the internet connection. (Final configuration of the router can be done later.)
2. Acceptance of contractor's work by the client and/or Deltares.
3. Mounting and aiming of cameras, and training of local support personnel.
4. Survey.

Survey

Once the cameras have been installed and definitely positioned, ground control points (GCPs) need to be surveyed, as well as the cameras themselves.

Deltares can help identify good GCPs based on snapshots and time exposure images if we are not physically present during or after installation.

For each camera 6-10 GCPs with a good distribution within its field of view is recommended. Absolute minimum is four GCPs, and more than twelve is probably overkill.

A good GCP is a fixed feature like corners of or on buildings, markings on roads, the bottoms of light poles, etc. Basically anything in view with good contrast that will not move during the course of the project can be a good GCP.

Sometimes a camera sees nothing other than sand, water and the horizon. In that case temporary, mobile GCPs are necessary. The basic procedure is that Argus snapshots are made of a surveyor's target while the surveyor records the coordinates. This is repeated several times within the fields of view of cameras. For each camera the snapshots are merged so that the surveyor appears multiple times, and positions are labeled for reference in the Argus processing software.

If a GCP is accessible to the surveyor satellite technology (GPS, GLONASS) can be used. A total station (http://en.wikipedia.org/wiki/Total_station) can be used to survey points that are not easily accessible. Surveyors that use only one technology or the other will restrict the choice of GCPs.