Requesting Imagery

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Detailed workflow for searching for satellite imagery and requesting it from the PGC.

DigitalGlobe Archive Search

The most effective way to search what has ever been collected by DigitalGlobe is through DigitalGlobe’s ImageFinder application.

This utility allows you to search the entire catalog through using either a map interface, gazetteer search, by entering coordinates, or by uploading a shapefile.

ImageFinder URL: https://browse.digitalglobe.com

Once you have established the area of interest (AOI) you are interested in, the search filter can be modified to retrieve only images that match your search criteria (e.g. cloud cover, date range, off-nadir angle, sensor).

When you initiate the search, a secondary window will appear with your results. This table can be sorted by any of the criteria that you have established, and the footprint outlines of the images will display on the map interface.

From here you can either download a shapefile of the images that you select or record the image Catalog IDs in a manner that works best for you.

DigitalGlobe ImageFinder
The map-based interface for DigitalGlobe’s ImageFinder. Source: DigitalGlobe, Inc.

Requests to the PGC

There are several ways to make a request for PGC imagery.

You Select the Imagery

Experienced users may prefer to search DigitalGlobe’s archive themselves using the ImageFinder application to determine the images they would like to request. Ultimately, PGC will need the image Catalog ID (or a list of Catalog IDs) in order to identify, retrieve, and deliver the imagery.

A DigitalGlobe Catalog ID is a 16-digit text/number string that uniquely identifies each image collected by one of the satellites. Catalog IDs can be sent to your PGC point of contact through email, as a text document or attachment, or as shapefiles that contain the Catalog ID as an attribute field.

PGC Selects the Imagery

Other Users may prefer to have PGC staff select candidate images on their behalf. It is important to be as detailed as possible when describing your image requirements.

Some important criteria to describe include:

  • Area of interest (described in coordinate boundaries, location with radius, or provided as a GIS point, line, or polygon file)
  • Date or year range (from X to X)
  • Seasonal criteria (e.g. only summer images, etc.)
  • Acceptable cloud cover percentage
  • Acceptable snow cover
  • Acceptable off-nadir angle
  • Spectral mode – Panchromatic or Multispectral
  • Multispectral bands – is 8-band or 4-band multispectral imagery needed?

Your PGC point of contact can assist with any questions or make recommendations based on your intended use.

Summary

In this Guide, we’ve covered:

  • Navigating DigitalGlobe’s ImageFinder tool
  • Requesting scenes by a list of Catalog IDs
  • Request parameters for an area-of-interest

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