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Orthorectified Photomosaic Leaf-on FAQ Metadata

Frequently-anticipated questions:


What does this data set describe?

Title:
Colonial National Historical Park Vegetation Mapping Project - Color Infrared Orthorectified Photomosaic Leaf-on
Abstract:
Orthorectified color infrared ERDAS Imagine image of Colonial National Historical Park. Produced from 328 color infrared photos taken October 26, 2001. Orthorectification accomplished with Imagine Orthobase v8.5 software. RMSE is 1.047 meters meeting class 1 NMAS. The fall mosaics for Colonial NHP are broken into 5 pieces due to space constraints. The 5 individual pieces are listed as follows: jamestown_swannpt_fa, greenspring_fa, parkway_ringfield_fa, williamsburg_fa, yorktown_fa.
  1. How should this data set be cited?

    North Carolina State University, Center for Earth Observation, 20030301, Colonial National Historical Park Color Infrared Orthorectified Photomosaic - Fall (leaf-on) (ERDAS Imagine IMG and MrSID formats).

    Online Links:

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -76.846093
    East_Bounding_Coordinate: -76.476366
    North_Bounding_Coordinate: 37.304531
    South_Bounding_Coordinate: 37.184082
    Description_of_Geographic_Extent: Colonial National Historical Park and environs

  3. What does it look like?

  4. Does the data set describe conditions during a particular time period?

    Calendar_Date: 26-Oct-2001
    Currentness_Reference: ground condition

  5. What is the general form of this data set?

    Geospatial_Data_Presentation_Form: remote-sensing image

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Raster data set.

    2. What coordinate system is used to represent geographic features?

      The map projection used is Transverse Mercator.

      Projection parameters:
      Scale_Factor_at_Central_Meridian: 0.999600
      Longitude_of_Central_Meridian: -75.000000
      Latitude_of_Projection_Origin: 0.000000
      False_Easting: 500000.000000
      False_Northing: 0.000000

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.000064
      Ordinates (y-coordinates) are specified to the nearest 0.000064
      Planar coordinates are specified in meters

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

  7. How does the data set describe geographic features?

    Entity_and_Attribute_Overview:
    Dataset consists of a raster 3 band color image. The bands are blue, green and near infrared. Each pixel contains a value between 0 - 255.
    Entity_and_Attribute_Detail_Citation: none


Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

    • North Carolina State University, Center for Earth Observation

  2. Who also contributed to the data set?

    Bill Millinor

  3. To whom should users address questions about the data?

    Sara Stevens
    Colonial NHP
    Data Manager
    200 Chestnut Street
    Philadelphia, Pennsylvania 19106
    USA

    (401) 874-4548 (voice)
    Sara_Stevens@nps.gov


Why was the data set created?

The dataset was developed for use by Colonial NHP as a GIS component and for digital monoplotting and mapping.


How was the data set created?

  1. From what previous works were the data drawn?

    dem (source 1 of 2)
    (<http://ned.usgs.gov/>), USGS, unknown, 30 Meter Digital Elevation Model- USGS National Elevation Dataset.

    Type_of_Source_Media: online
    Source_Scale_Denominator: 30 meter
    Source_Contribution: elevation

    photos (source 2 of 2)
    Kucera Internation, Inc, Unpublished Material, Aerial photographs of Colonial NHP.

    Type_of_Source_Media: color ir aerial transparencies
    Source_Scale_Denominator: 6000
    Source_Contribution: Aerial view of Colonial NHP

  2. How were the data generated, processed, and modified?

    Date: Nov-2002 (process 1 of 1)
    The photos (328 total) were used to create an orthorectified mosaic using ERDAS Imagine. The photos were scanned at 600 dpi and imported into Imagine. The DEMs were resampled from 30 meters to 10 meters in ArcInfo Workstation using cubic convolution and then mosaicked together. If the mosaicked DEMs had gaps, they were then run in ArcInfo Workstation using a focal mean. The images were orthorectified using ERDAS Imagine Orthobase software. Airborne GPS and IMU data were used in the aerial triangulation procedure. Aerial triangulation produced a single RMSE of less than 1 meter for the entire block of photos. The orthorectified images were then mosaiced within Imagine or Er Mapper to form one seamless basemap image for Colonial National Historical Park. The mosaic was compressed using MrSID software at a 1:20 target compression ratio.

    Person who carried out this activity:

    NCSU, Center for Earth Observation
    NCSU, Center For Earth Observation
    NCSU Campus Box 7106
    Raleigh, NC 27695-7106
    USA

    919-515-3430 (voice)
    919-515-3439 (FAX)

  3. What similar or related data should the user be aware of?


How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

  2. How accurate are the geographic locations?

    Overall positional accuracy of 1.047 meters based on root mean square error meets Class 1 NMAS. Horizontal accuracy was assessed on the basis of 57 field survey points distributed throughout the image. The actual field coordinates for these points were recorded with a Trimble ProXRS GPS unit with real-time differential correction with a minimum of 180 fixes per point. The field coordinates were then post-processed using differential correction. The field coordinates were then compared to the image mosaic coordinates for these points, determined in ESRI ArcView 3.3 software.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    Colonial National Historical Park and surrounding area

  5. How consistent are the relationships among the observations, including topology?

    Raster Data


How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints: none
Use_Constraints: none

  1. Who distributes the data set? (Distributor 1 of 1)

    USGS/CSS/Core Science Analytics and Synthesis
    c/o USGS-NPS Vegetation Mapping Program Coordinator
    Denver Federal Center, Building 810, Room 8000, MS 302
    Denver, Colorado 80225

    (303) 202-4220 (voice)
    303-202-4219 (FAX)
    gs-b-npsveg@usgs.gov

  2. What's the catalog number I need to order this data set?

    Orthorectified 3 band color infrared image of Colonial National Historical Park.

  3. What legal disclaimers am I supposed to read?

    The U.S. Geological Survey and the National Park Service shall not be held liable for improper or incorrect use of the data described and/or contained herein. These data and related graphics (if available) are not legal documents and are not intended to be used as such.

    The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived. It is the responsibility of the data user to use the data appropriately and consistent within the limitations of geospatial data in general and these data in particular. Any related graphics (if available) are intended to aid the data user in acquiring relevant data; it is not approriate to use the related graphics as data.

    The U.S. Geological Survey and the National Park Service gives no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data. It is strongly recommended that these data are directly acquired from an U.S. Geological Survey and National Park Service servers and not indirectly through other sources which may have changed the data in some way. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the utility of the data on another system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data. It is also strongly recommended that careful attention be paid to the contents of the metadata file associated with these data. Mention of trade names or commercial products in this metadata report does not constitute endorsement or recommendation for use by the U. S. Department of the Interior, U. S. Geological Survey and National Park Service.

  4. How can I download or order the data?


Who wrote the metadata?

Dates:
Last modified: 15-Sep-2003
Last Reviewed: 18-May-2010
Metadata author:
USGS/CSS/Core Science Analytics and Synthesis
c/o USGS-NPS Vegetation Mapping Program Coordinator
Denver Federal Center, Building 810, Room 8000, MS 302
Denver, Colorado 80225

(303) 202-4220 (voice)
303-202-4219 (FAX)
gs-b-npsveg@usgs.gov

Metadata standard:
FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata (FGDC-STD-001.1-1999)
Metadata extensions used:


Generated by mp version 2.9.12 on Tue May 18 12:59:20 2010

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