This Working Group is responsible for maintaining an inventory of the status of orthophotography (aerial imagery) at the county level. It is charged with seeking sources of funding to assist counties and state agencies in acquiring high resolution imagery. High-resolution color orthophotography (half-foot or one-foot pixel resolution) is used extensively by local and state government agencies. It is flown during the winter months to achieve better ground visibility (leaf-off conditions). The Working Group develops procedures for the distribution of this aerial imagery within a network of state government agencies.
New Technical Specifications for NC Orthophotos. The “Technical Specifications for Base, Cadastral and Digital Mapping (Orthophotos),” developed by the North Carolina Land Records Management Program, has been revised and adopted as the official standard for digital orthophotography. The Geographic Information Coordinating Council adopted the revised standard on August 12, 2009, and the Office of the Secretary of State declared it the official standard for all county and municipal mapping projects on October 1, 2009.
The US Department of Agriculture also flies color orthophotography (one-meter pixel resolution) to capture crop and agricultural conditions in the summer. North Carolina partnered with USDA for a 2008 summer flight by the National Agriculture Imagery Program (NAIP). Compressed images, by county mosaic, are now available from the NC Department of Agriculture and Consumer Services. Contact Dan Madding.
To understand “best practices” for the NAIP program image processing, consult this document.
Large-format digital camera technology is rapidly replacing the large-scale aerial imagery previously captured by aerial film collection. The current North Carolina Land Record Specifications were created for and are related to aerial film collection of orthophotography. A White Paper prepared by the Orthophotography Planning Work Group and presented to the Geographic Information Coordinating Council in August 2008 presents the differences between film and digital collection of that photography. Read more. To see the photographic differences from the two types of cameras, click here.
To learn more about modern photogrammetry, here are two PowerPoints prepared by the NC Department of Transportation:
Photogrammetry Workshop: Basics of Modern Photogrammetry (Oct 2007), and the 2008 Review Officers Workshop.
The current Chair is Gary Thompson (919.733.3836).