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National High Altitude Photography (NHAP) Data Dictionary

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By Earth Resources Observation and Science (EROS) Center July 19, 2021

The Data Dictionaries are a set of information describing the contents, format, and structure of elements for EarthExplorer products.

 

Acceptance Code

  • Field Definition:  The USGS/EROS NHAP frames table includes codes that denote information regarding the acceptance status of each frame as rated by the NHAP project office.

               Values:
               OK = OK = Accepted
               FC = Fiducials Corner = Camera Issues
               OX = N/A = Camera Issues
               PD = N/A = Camera Issues
               VF = Vacuum Failure = Camera Issues
               VT = N/A = Camera Issues
               C = Clouds = Cloud Cover
               CC = Cloud Cover? = Cloud Cover
               CT = Contrail = Cloud Cover
               FL = Flooding = Cloud Cover
               S = Smoke = Cloud Cover
               SH = Shadows = Cloud Cover
               SW = Snow = Cloud Cover
               WC = Missed Center? = Coverage Faults
               EC = Excessive Crab = Coverage Faults
               IC = Insufficient Coverage = Coverage Faults
               IND = N/A = Coverage Faults
               IQ = N/A = Coverage Faults
               MC = Missed Center = Coverage Faults
               QM = Quad Min? = Coverage Faults
               QN = N/A = Coverage Faults
               RO = Run Off = Coverage Faults
               SE = N/A = Coverage Faults
               TL = Tilt = Coverage Faults
               WM = N/A = Coverage Faults
               #-5 = N/A = Exposure Faults
               #1 = N/A = Exposure Faults
               #2 = N/A = Exposure Faults
               #26 = N/A = Exposure Faults
               #7 = N/A = Exposure Faults
               #92 = N/A = Exposure Faults
               * = N/A = Exposure Faults
               1 = N/A = Exposure Faults
               +2 2 = N/A = Exposure Faults
               +3 2 = N/A = Exposure Faults
               +4 3 = N/A = Exposure Faults
               +5 1 = N/A = Exposure Faults
               / 47 = N/A = Exposure Faults
               1 1 = N/A = Exposure Faults
               11 1 = N/A = Exposure Faults
               118 1 = N/A = Exposure Faults
               119 1 = N/A = Exposure Faults
               124 2 = N/A = Exposure Faults
               130 1 = N/A = Exposure Faults
               136 1 = N/A = Exposure Faults
               145 1 = N/A = Exposure Faults
               146 1 = N/A = Exposure Faults
               154 1 = N/A = Exposure Faults
               16 1 = N/A = Exposure Faults
               161 1 = N/A = Exposure Faults
               169 1 = N/A = Exposure Faults
               183 1 = N/A = Exposure Faults
               1M 1 = N/A = Exposure Faults
               21 1 = N/A = Exposure Faults
               29 1 = N/A = Exposure Faults
               3-B 1 = N/A = Exposure Faults
               31 = N/A = Exposure Faults
               34 = N/A = Exposure Faults
               35 = N/A = Exposure Faults
               41 = N/A = Exposure Faults
               59 = N/A = Exposure Faults
               65 = N/A = Exposure Faults
               7 = N/A = Exposure Faults
               80 = N/A = Exposure Faults
               81 = N/A = Exposure Faults
               88 = N/A = Exposure Faults
               98 = N/A = Exposure Faults
               CD = N/A = Exposure Faults
               HS = N/A = Exposure Faults
               I = N/A = Exposure Faults
               BH = Base Height Ratio = Exposure Faults
               CB = Color Balance = Exposure Faults
               D+L = Dmin Low = Exposure Faults
               DL = Dmin Low = Exposure Faults
               DM = Dmin Low = Exposure Faults
               DNH = Dmin High = Exposure Faults
               DNL = N/A = Exposure Faults
               DRL = N/A = Exposure Faults
               DXH = D Range Low = Exposure Faults
               DnH = Dmin High = Exposure Faults
               DnL = Dmin Low = Exposure Faults
               DrL = D Range Low = Exposure Faults
               DxH = Dmax High = Exposure Faults
               HR = Base Height Ratio = Exposure Faults
               MD = Misc Defects = Exposure Faults
               NS = N/A = Exposure Faults
               O = Other? = Exposure Faults
               SF = Scratched Failure = Exposure Faults
 

Acquisition Date

  • Field Definition:  The acquisition date refers to the date the image was acquired.

               Format:
               YYYY/MM/DD
               YYYY = Year
               MM = Month
               DD = Day
 

Coordinates - Decimal Degrees

  • Field Definition:  NHAP photographs are acquired over predetermined center points (center latitude and center longitude) which are defined by their location within a 7.5-minute quadrangle. The NAPP images are flown north to south or south to north. The latitude and longitude are provided in decimal degrees for the following fields:

                 Values:      
                 Scene Center Latitude and Longitude
                 Northeast (NE) Corner Latitude and Longitude
                 Northwest (NW) Corner Latitude and Longitude
                 Southeast (SE) Corner Latitude and Longitude
                 Southwest (SW) Corner Latitude and Longitude

                 Latitude Format Decimal Degrees: -90.000 through 90.000
                 Longitude Format Decimal Degrees: -180.000 through 180.000

                 Number of decimal places will vary by dataset – check collection in EE.
 

Coordinates - Degrees, Minutes, Seconds

  • Field Definition:  NHAP photographs are acquired over predetermined center points (center latitude and center longitude) which are defined by their location within a 7.5-minute quadrangle. The NAPP images are flown north to south or south to north. The latitude and longitude are provided in degrees, minutes, and seconds for the following fields:

                 Values:
                 Scene Center Latitude and Longitude
                 Northeast (NE) Corner Latitude and Longitude
                 Northwest (NW) Corner Latitude and Longitude
                 Southeast (SE) Corner Latitude and Longitude
                 Southwest (SW) Corner Latitude and Longitude

                Longitude Format:
                DDDMMSS.SSH
                DDD = Degree(s) with a range of 0 through 180
                MM = Minute(s) with a range of 0 through 59
                SS.SS = Second(s) with a range of 0 through 59.99
                H = Hemisphere with E for east and W for west

                Latitude Format:
                DDMMSS.SSH
                DD = Degree(s) with a range of 0 through 90
                MM = Minutes(s) with a range of 0 through 59
                SS.SS = Second(s) with a range of 0 through 59.99
                H = Hemisphere with N for north and S for south
 

County

  • Field Definition:  This field is used to identify the county in in which the photograph was acquired.
     

Entity ID

  • Field Definition:  This field is used to identify data by assigning a unique series of letters and numbers to an image.

              Format:
              DDAPPPPPPRRRRFFF
              DD = Data Set Identifier (NB for black & white, NC for color infrared)
              A = Agency where 1 indicates USGS
              PPPPPP = Project
              RRRR = Roll Number*
              FFF = Frame Number*

              * Depending upon the entity ID, some of the information may be preceded by zero-filled spaces.

              Example:
              NC1NHAP840053084
 

Film Type

  • Field Definition:  The type of film used for aerial mapping and interpretation included black-and-white and color infrared. Black-and-white (B&W) panchromatic film is sensitive to the full visible portion of the electromagnetic spectrum of light and captures images in tones of gray ranging from black to white. Color infrared (CIR), or false color, film is sensitive to green and red in the visible portion of spectrum of light and extends into the near-infrared region of the spectrum. CIR photography utilizes high speed film that is subject to degradation prior to processing, which can create an overall blue cast to the image.

              Valid Codes:
              B&W = Black-and-White
              CIR = Color Infrared
 

Frame

  • Field Definition:  The number assigned to a photographic frame on a roll of film.
     

High Resolution Download Available

  • Field Definition:  This field indicates if a high resolution download is currently available for the product. Standard high resolution products are at a resolution of 25 microns or 1,000 dots per inch (dpi). Medium resolution products are at a resolution of 63 microns or 400 dpi.

    Note: EarthExplorer will have a shopping basket icon on the results page for images that are available for on-demand scanning. Black and White images are available at 25 microns (1,000 dpi), 14 microns (1,800 dpi), or 7 microns (3,600 dpi). Color images are limited to 25 microns or 14 microns due to file size.
     

High Resolution Source

  • Field Definition:  NHAP imagery is currently archived with USGS/EROS and the USDA's Aerial Photography Field Office (APFO). Both EROS and APFO are scanning the NHAP film to improve data availability to end users. This field identifies which organization made the original data capture for this frame of photography even though access is provided through EarthExplorer.
     

Nominal Focal Length

  • Field Definition:  An approximate value of the distance in inches measured along the lens axis from the rear nodal point to the imaging surface plane used for the classification of lenses.

              Values:
              6 inches for B&W
              8.25 inches for CIR
 

Project

  • Field Definition:  Name used to identify a project within the NHAP collection.

              Values:
              NHAP85 = NHAP followed by the year contracted
              NHAP02 = NHAP second cycle
 

Roll

  • Field Definition:  The number assigned to a roll of film.
     

Scale

  • Field Definition:  The black-and-white film was exposed in a precision aerial camera with a focal length of 6 inches (15.3 cm) and produced a photograph at a scale of 1 80,000 (1 inch equals about 1.25 miles). Each black-and-white exposure covers nearly 130 square miles of terrain. The color infrared film was exposed in a second aerial camera with a focal length of 8.25 inches (21.0 cm) and produced a photograph at a scale of 1 to 58,000 (1 inch equals about 0.9 miles). Each color infrared exposure covers nearly 68 square miles of terrain.
     

State

  • Field Definition:  The location in which the imagery was acquired.

The Data Dictionaries are a set of information describing the contents, format, and structure of elements for EarthExplorer products.

 

Acceptance Code

  • Field Definition:  The USGS/EROS NHAP frames table includes codes that denote information regarding the acceptance status of each frame as rated by the NHAP project office.

               Values:
               OK = OK = Accepted
               FC = Fiducials Corner = Camera Issues
               OX = N/A = Camera Issues
               PD = N/A = Camera Issues
               VF = Vacuum Failure = Camera Issues
               VT = N/A = Camera Issues
               C = Clouds = Cloud Cover
               CC = Cloud Cover? = Cloud Cover
               CT = Contrail = Cloud Cover
               FL = Flooding = Cloud Cover
               S = Smoke = Cloud Cover
               SH = Shadows = Cloud Cover
               SW = Snow = Cloud Cover
               WC = Missed Center? = Coverage Faults
               EC = Excessive Crab = Coverage Faults
               IC = Insufficient Coverage = Coverage Faults
               IND = N/A = Coverage Faults
               IQ = N/A = Coverage Faults
               MC = Missed Center = Coverage Faults
               QM = Quad Min? = Coverage Faults
               QN = N/A = Coverage Faults
               RO = Run Off = Coverage Faults
               SE = N/A = Coverage Faults
               TL = Tilt = Coverage Faults
               WM = N/A = Coverage Faults
               #-5 = N/A = Exposure Faults
               #1 = N/A = Exposure Faults
               #2 = N/A = Exposure Faults
               #26 = N/A = Exposure Faults
               #7 = N/A = Exposure Faults
               #92 = N/A = Exposure Faults
               * = N/A = Exposure Faults
               1 = N/A = Exposure Faults
               +2 2 = N/A = Exposure Faults
               +3 2 = N/A = Exposure Faults
               +4 3 = N/A = Exposure Faults
               +5 1 = N/A = Exposure Faults
               / 47 = N/A = Exposure Faults
               1 1 = N/A = Exposure Faults
               11 1 = N/A = Exposure Faults
               118 1 = N/A = Exposure Faults
               119 1 = N/A = Exposure Faults
               124 2 = N/A = Exposure Faults
               130 1 = N/A = Exposure Faults
               136 1 = N/A = Exposure Faults
               145 1 = N/A = Exposure Faults
               146 1 = N/A = Exposure Faults
               154 1 = N/A = Exposure Faults
               16 1 = N/A = Exposure Faults
               161 1 = N/A = Exposure Faults
               169 1 = N/A = Exposure Faults
               183 1 = N/A = Exposure Faults
               1M 1 = N/A = Exposure Faults
               21 1 = N/A = Exposure Faults
               29 1 = N/A = Exposure Faults
               3-B 1 = N/A = Exposure Faults
               31 = N/A = Exposure Faults
               34 = N/A = Exposure Faults
               35 = N/A = Exposure Faults
               41 = N/A = Exposure Faults
               59 = N/A = Exposure Faults
               65 = N/A = Exposure Faults
               7 = N/A = Exposure Faults
               80 = N/A = Exposure Faults
               81 = N/A = Exposure Faults
               88 = N/A = Exposure Faults
               98 = N/A = Exposure Faults
               CD = N/A = Exposure Faults
               HS = N/A = Exposure Faults
               I = N/A = Exposure Faults
               BH = Base Height Ratio = Exposure Faults
               CB = Color Balance = Exposure Faults
               D+L = Dmin Low = Exposure Faults
               DL = Dmin Low = Exposure Faults
               DM = Dmin Low = Exposure Faults
               DNH = Dmin High = Exposure Faults
               DNL = N/A = Exposure Faults
               DRL = N/A = Exposure Faults
               DXH = D Range Low = Exposure Faults
               DnH = Dmin High = Exposure Faults
               DnL = Dmin Low = Exposure Faults
               DrL = D Range Low = Exposure Faults
               DxH = Dmax High = Exposure Faults
               HR = Base Height Ratio = Exposure Faults
               MD = Misc Defects = Exposure Faults
               NS = N/A = Exposure Faults
               O = Other? = Exposure Faults
               SF = Scratched Failure = Exposure Faults
 

Acquisition Date

  • Field Definition:  The acquisition date refers to the date the image was acquired.

               Format:
               YYYY/MM/DD
               YYYY = Year
               MM = Month
               DD = Day
 

Coordinates - Decimal Degrees

  • Field Definition:  NHAP photographs are acquired over predetermined center points (center latitude and center longitude) which are defined by their location within a 7.5-minute quadrangle. The NAPP images are flown north to south or south to north. The latitude and longitude are provided in decimal degrees for the following fields:

                 Values:      
                 Scene Center Latitude and Longitude
                 Northeast (NE) Corner Latitude and Longitude
                 Northwest (NW) Corner Latitude and Longitude
                 Southeast (SE) Corner Latitude and Longitude
                 Southwest (SW) Corner Latitude and Longitude

                 Latitude Format Decimal Degrees: -90.000 through 90.000
                 Longitude Format Decimal Degrees: -180.000 through 180.000

                 Number of decimal places will vary by dataset – check collection in EE.
 

Coordinates - Degrees, Minutes, Seconds

  • Field Definition:  NHAP photographs are acquired over predetermined center points (center latitude and center longitude) which are defined by their location within a 7.5-minute quadrangle. The NAPP images are flown north to south or south to north. The latitude and longitude are provided in degrees, minutes, and seconds for the following fields:

                 Values:
                 Scene Center Latitude and Longitude
                 Northeast (NE) Corner Latitude and Longitude
                 Northwest (NW) Corner Latitude and Longitude
                 Southeast (SE) Corner Latitude and Longitude
                 Southwest (SW) Corner Latitude and Longitude

                Longitude Format:
                DDDMMSS.SSH
                DDD = Degree(s) with a range of 0 through 180
                MM = Minute(s) with a range of 0 through 59
                SS.SS = Second(s) with a range of 0 through 59.99
                H = Hemisphere with E for east and W for west

                Latitude Format:
                DDMMSS.SSH
                DD = Degree(s) with a range of 0 through 90
                MM = Minutes(s) with a range of 0 through 59
                SS.SS = Second(s) with a range of 0 through 59.99
                H = Hemisphere with N for north and S for south
 

County

  • Field Definition:  This field is used to identify the county in in which the photograph was acquired.
     

Entity ID

  • Field Definition:  This field is used to identify data by assigning a unique series of letters and numbers to an image.

              Format:
              DDAPPPPPPRRRRFFF
              DD = Data Set Identifier (NB for black & white, NC for color infrared)
              A = Agency where 1 indicates USGS
              PPPPPP = Project
              RRRR = Roll Number*
              FFF = Frame Number*

              * Depending upon the entity ID, some of the information may be preceded by zero-filled spaces.

              Example:
              NC1NHAP840053084
 

Film Type

  • Field Definition:  The type of film used for aerial mapping and interpretation included black-and-white and color infrared. Black-and-white (B&W) panchromatic film is sensitive to the full visible portion of the electromagnetic spectrum of light and captures images in tones of gray ranging from black to white. Color infrared (CIR), or false color, film is sensitive to green and red in the visible portion of spectrum of light and extends into the near-infrared region of the spectrum. CIR photography utilizes high speed film that is subject to degradation prior to processing, which can create an overall blue cast to the image.

              Valid Codes:
              B&W = Black-and-White
              CIR = Color Infrared
 

Frame

  • Field Definition:  The number assigned to a photographic frame on a roll of film.
     

High Resolution Download Available

  • Field Definition:  This field indicates if a high resolution download is currently available for the product. Standard high resolution products are at a resolution of 25 microns or 1,000 dots per inch (dpi). Medium resolution products are at a resolution of 63 microns or 400 dpi.

    Note: EarthExplorer will have a shopping basket icon on the results page for images that are available for on-demand scanning. Black and White images are available at 25 microns (1,000 dpi), 14 microns (1,800 dpi), or 7 microns (3,600 dpi). Color images are limited to 25 microns or 14 microns due to file size.
     

High Resolution Source

  • Field Definition:  NHAP imagery is currently archived with USGS/EROS and the USDA's Aerial Photography Field Office (APFO). Both EROS and APFO are scanning the NHAP film to improve data availability to end users. This field identifies which organization made the original data capture for this frame of photography even though access is provided through EarthExplorer.
     

Nominal Focal Length

  • Field Definition:  An approximate value of the distance in inches measured along the lens axis from the rear nodal point to the imaging surface plane used for the classification of lenses.

              Values:
              6 inches for B&W
              8.25 inches for CIR
 

Project

  • Field Definition:  Name used to identify a project within the NHAP collection.

              Values:
              NHAP85 = NHAP followed by the year contracted
              NHAP02 = NHAP second cycle
 

Roll

  • Field Definition:  The number assigned to a roll of film.
     

Scale

  • Field Definition:  The black-and-white film was exposed in a precision aerial camera with a focal length of 6 inches (15.3 cm) and produced a photograph at a scale of 1 80,000 (1 inch equals about 1.25 miles). Each black-and-white exposure covers nearly 130 square miles of terrain. The color infrared film was exposed in a second aerial camera with a focal length of 8.25 inches (21.0 cm) and produced a photograph at a scale of 1 to 58,000 (1 inch equals about 0.9 miles). Each color infrared exposure covers nearly 68 square miles of terrain.
     

State

  • Field Definition:  The location in which the imagery was acquired.
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