What is Remote Sensing

Back to HomePage

A means of acquiring information using airborne equipment and techniques to determine the characteristics of an area. Aerial photographs from aircraft and satellite are the most common form of remote sensing.

The project extent (area size, geographycal co-ordinates) determines the type of remote sensed images that will be suitable for the GIS project. Basically if you have a small area that needs to be incorporated into a GIS then aerial photographs are a sensible solution, where as satellite image are reserved for relative large areas.

Remote Digitising illustration

There are also a diverse amount of satellite imagery to select from, a ''LandSat" satellite has several sensors which allows it to record a range of wavelengths that is categorised in 7 bands/categories each with it's own ''color'' some of these colors aren't visible to the naked eye such as "near infrared" (detect vegetation as a red color) and "thermal infrared" (detects heat omitted from the earth surface). Satellites are complex images and covers large areas, not to mention its resolution capabilities that its possible to read your number plate from a high resolution satellite image taken above the earths stratosphere.
Basically aerial photographs are simple and cost effective. The same analysis can be done on both images. For illustration purposes and simplicity I have used aerial photographs to illustrate some basic uses of remote sensing in GIS.

Remote Digitising illustration