Producing Colour Corrected Surface Brightness Images

By default, flux density values calculated by IRAS90 assume that the flux density emitted by the source is inversely proportional to frequency. Adjusting quoted flux density values to refer to some other known source spectrum is known as ``colour correction'' and is described in the IRAS Catalogs and Atlases Explanatory Supplement, page VI-27. The application COLCORR produces colour corrected images assuming that the source spectrum is that of an optically thin greybody. The user should first produce colour temperature and optical depth maps using the recipe described in section , and these should then be given as input to COLCORR.