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LiDAR_ShadedRelief (Map Service)


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Current Version: 10.81

Service Description:

This shaded relief image was generated from the lidar-based bare-earth digital elevation model (DEM). A shaded relief image provides an illustration of variations in elevation using artificial shadows. Based on a specified position of the sun, areas that would be in sunlight are highlighted and areas that would be in shadow are shaded. In this instance, the position of the sun was assumed to be 45 degrees above the northwest horizon.

The shaded relief image shows areas that are not in direct sunlight as shadowed. It does not show shadows that would be cast by topographic features onto the surrounding surface.

Using ERDAS IMAGINE, a 3X3 neighborhood around each pixel in the DEM was analyzed, and a comparison was made between the sun's position and the angle that each pixel faces. The pixel was then assigned a value between -1 and +1 to represent the amount of light reflected. Negative numbers and zero values represent shadowed areas, and positive numbers represent sunny areas. In ArcGIS Desktop 10.7.1, the image was converted to a JPEG 2000 format with values from 0 (black) to 255 (white).

See the MassGIS datalayer page to download the data as a JPEG 2000 image file.

View this service in the Massachusetts Elevation Finder.

MassGIS has also published a Lidar Shaded Relief image service from ArcGIS Server.



Map Name: Map

Legend

All Layers and Tables

Layers: Tables: Description:

This shaded relief image was generated from the lidar-based bare-earth digital elevation model (DEM). A shaded relief image provides an illustration of variations in elevation using artificial shadows. Based on a specified position of the sun, areas that would be in sunlight are highlighted and areas that would be in shadow are shaded. In this instance, the position of the sun was assumed to be 45 degrees above the northwest horizon.

The shaded relief image shows areas that are not in direct sunlight as shadowed. It does not show shadows that would be cast by topographic features onto the surrounding surface.

Using ERDAS IMAGINE, a 3X3 neighborhood around each pixel in the DEM was analyzed, and a comparison was made between the sun's position and the angle that each pixel faces. The pixel was then assigned a value between -1 and +1 to represent the amount of light reflected. Negative numbers and zero values represent shadowed areas, and positive numbers represent sunny areas. In ArcGIS Desktop 10.7.1, the image was converted to a JPEG 2000 format with values from 0 (black) to 255 (white).

See the MassGIS datalayer page to download the data as a JPEG 2000 image file.

View this service in the Massachusetts Elevation Finder.

MassGIS has also published a Lidar Shaded Relief image service from ArcGIS Server.



Copyright Text: MassGIS

Spatial Reference:
102100

Single Fused Map Cache: true

Capabilities: Map,TilesOnly

Tile Info:
Initial Extent:
Full Extent:
Min Scale: 1.47914382E8
Max Scale: 0.0

Min LOD: 0
Max LOD: 23

Units: esriMeters

Supported Image Format Types: MIXED

Export Tiles Allowed: true
Max Export Tiles Count: 100000

Document Info: