The spectrophotometric mode was dedicated to obtaining low resolution spectra of broad spectral features such as dust and polyaromatic hydrocarbon (PAH) features. This mode was also used for detection of faint atomic or ionic lines, but the intensity was contained in only 1 or 2 pixels, thus this did not allow the determination of the line profile. For this purpose the SWS instrument (see ISO Handbook Volume V on SWS, [34]) was recommended. For extended sources it was possible to perform spectrophotometry in a spacecraft raster.