A viewshed shows you the areas that are visible (or invisible) from a particular XY point (the "transmitter"). You can select the view area you wish to sample (radius, start and sweep angle), set the transmitter and receiver heights and include any obstructions, and choose to show visible areas or invisible areas. Viewshed analysis is useful in many applications, such as determining if mining operations or drill rigs can be viewed from public locations, determining what is visible from trails or roads, and to locate communication towers.
To create a viewshed, all you need is a grid file. Create any 2D map type from the grid (e.g. Home | New Map | Contour Map), then select the map and click Map | Add to Map | Layer | Viewshed and click on the map where you want the transmitter or origin location to be. A Viewshed layer is added to the Contents window and the visible areas from that transmitter location are shaded in green. You can select the viewshed layer in the Contents window and edit properties, including the transmitter location, in the Properties window.
We have some other resources to help explain viewsheds:
- Surfer 13 New Feature Series: Viewshed Maps blog
- How can I create a viewshed in Surfer? knowledge base article
- How can I join two DEM files in Surfer, so I can create a viewshed over both? knowledge base article
- Do Surfer viewsheds account for the curvature of the earth? knowledge base article
Updated September 1, 2020