GOES imagery is available to users in either 10-bit GOES Variable (GVAR) counts or 8-bit brightness (or display) counts. The process of converting raw satellite values into 10-bit values is called calibration and is explained at: http://www.nnic.noaa.gov/SOCC/goescal.html. The non-linear process of converting from 10-bit to 8-bit values is called scaling and is explained at: http://www.cira.colostate.edu/RAMM/cal_val/calib.htm

Traditionally, infrared images are enhanced in the opposite sense compared with visible imagery. In visible imagery, the lower energy portions are displayed as dark and the higher energy portions as bright. For infrared imagery , the opposite is true. This is done so that clouds which are highly reflective in the visible imagery and cold in the infrared imagery appear bright in both. It has also been determined that color enhancements are often the best way to highlight important features in the infrared and water vapor imagery.

The starting point for an explanation of the enhancement of each channel in this section of the tutorial are images in 8-bit (0-255) counts. Below are paths to examples of image enhancements used for each of the GOES Imager channels 1 through 5: