2008 OrthoImagery of Coastal North Carolina

Simple download of data files.

Date that the source FGDC record was last modified.

Converted from FGDC (Federal Geographic Data Committee) CSDGM (Content Standard for Digital Geospatial Metadata) (version FGDC-STD-001-1998) using 'fgdc_to_inport_xml.pl' script. Contact Tyler Christensen (NOS) for details.

Partial upload of Positional Accuracy fields only.

Partial upload to move data access links to Distribution Info.

Used to provide ground elevations for orthorectification process. | Type of Source Media: external hard drive

Used to provide photo exterior orientations for orthorectification process. | Type of Source Media: external hard drive

Dewberry 's Raleigh, North Carolina office acquired photo identifiable ground control points during the acquisition of aerial imagery. The ground control points were established under the guidance of Buddy Lee, a Professional Land Surveyor in the State of North Carolina. | Type of Source Media: external hard drive

Source imagery for orthophoto production. | Type of Source Media: digital tape media

The photography was captured by a Z/I DMC (Digital Modular Camera) system at 24,000' AMT (Above Mean Terrain). The photography was captured over 2 flying seasons. Flight lines 38, 39, 41, 42, 43, 44 and 45 were captured on 10/12/2007. Flight lines 33, 34, 35, 36, 37, 51, 52, 53, 54, 55, 56, 58, 59, 60 and 61 were captured on 10/13/2007. Flight lines 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 and 15 were captured on 10/14/2007. Flight lines 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 and 32 were captured on 10/15/2007. Flight lines 31, 40, 46, 47, 48, 49, 50 and 57 were captured on 05/27/2008. The DMC images were aerotriangulated to support digital ortho image production for the coast of North Carolina and Southeastern Virginia. Airborne GPS and ground check point data was provided by AERO-METRIC, Inc. The project was referenced to the North American Datum of 1983 (NAD83) with the 2007 NSRS Adjustment, State Plane Coordinate System 1983, North Carolina horizontally and to the North American Vertical Datum of 1988 (NAVD88) vertically. Units were in Meters. The DMC images, ABGPS data, and ground check point data were used as inputs to the Zeiss/Intergraph ImageStation Automatic Triangulation (ISAT) softcopy program. ISAT correlated image points and aerotriangulated the block of images to create exposure station exterior orientations. All ground checkpoints were manually measured on the imagery. These ground checkpoints were included in the aerotriangulation adjustments as unconstrained points for absolute ground location verification. Rectification was done using the aerotriangulation data, raw DMC images, and DEM data provided by the North Carolina Floodplain Mapping Program (NCFMP). The DEM data was developed using LiDAR technology for specific floodplain mapping applications across the entire State of North Carolina. The LiDAR data was gridded to a 20 meter raster Digital Elevation Model (DEM). These rectified images were used to draw seamlines. The rectified images were mosaicked, balanced, and cut into final image sheets. The final sheets were viewed and artifacts were removed as well as other edits performed. To help with SAV interpretation, individual orthophoto frames, named by flightline and frame, were delivered with the mosaicked orthophotos corresponding to the USGS DOQQ tile grid. Dewberry performed an independent QC of the imagery. Horizontal Accuracy was determined by comparing the coordinates of surveyed photo identifiable points to the coordinates of those points from the orthoimagery. A qualitative review of the orthoimagery was also performed to ensure the dataset was free of major discrepancies or issues such as cloud clover, mis-aligned bands, voids, water glint, and whitecaps and to ensure the dataset met the projects requirements and needs.