標準號：IS 6650-1972
發布日期：1973/1/1 12:00:00
實施日期：1999/12/31 12:00:00
適用范圍：1.1 This standard provides a method for quantitatively determining the thiosulphate content of processed photographic paper prints. The method is intended for use in the selection of prints with reference to their probable permanency and in the control or evaluation of processing.1.2 The method given in this standard is also valid and preferable as a means for determining any residual thiosulphate (and tetrathionate) in prints which have been treated with hypo-eliminators. Thus, the effectiveness of a given hypo-eliminator can be determined.