1.1 This practice covers the calibration of photographic emulsions and their use in measuring spectral line intensity ratios. Several methods of external illumination are outlined. Instructions are given for using regression in a computer program for defining the emulsion calibration from preliminary curves prepared by using the two-step and two-line methods and the in-line group procedure. Correction for spectral background is discussed in some detail, and instructions are given for preparing analytical curves.

1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.