In order to select the appropriate spatial data, it is necessary to consider the information requirements of a specific application and the mapping purpose. Once the data requirements have been determined, the data availability, accessibility and costs must be investigated. The best source for existing aerial photographs is, in most cases, the national survey and mapping organisation.
This Unit provides trainees with basic knowledge about how to obtain Earth observation data. It starts with a description of data selection criteria and then discusses the availability and cost of images. A list of recommended online sources of imagery is provided as an additional resource in this Unit.
Unit objectives / expected outcomes
After the completion of the Unit the trainee will be able to:
- select the most useful remote sensing product for a mapping purpose using appropriate data selection criteria;
- choose imagery by balancing cost and quality of images;
- identify a good source for obtaining images and search for suitable imagery in online repositories.
Content outline, main topics covered and suggested sequencing
This Unit focuses on the topics listed below:
- Obtaining remote sensing images (PPT No. 1) (30 min)
- Accessing online sources of imagery (Exercise No.1) (90 min)
Components of the Unit
- Exercise No. 1: Accessing online sources of imagery; to expose trainees to searching for online imagery (90 min)
Handouts for Trainee (to be distributed in printed format):
Handouts for Trainee (to be distributed in digital format)
Additional trainer resources
- Tempfli, K., Kerle, N., Janssen, L.F. and Huurneman, G. (eds.), 2008, “Principles of Remote Sensing”, Fourth edition ISBN 90–6164–227–2, ITC, Enschede, The Netherlands.
Flip chart, marker pen, computers, broadband Internet connection, digital version of the file “List of Additional Resources”, which is part of this Unit