For some applications, such as calculating tristimulus values for a different observer or illuminant, it is useful
to have recourse to spectral data. As already stated it was deliberately decided not to standardize such data
since it can be very restrictive for ink manufacturing and future d evelopment of ink with improved propertie s.
However, the following data may be taken as “typical”. Since most inks are currently based on the same
pigments, any differences at the present time are likely to be small. It cannot be presupposed that standar d
pr inting inks necessarily comply with the data presented here. These values are derived from measurements
made on samples printed on the reference substrate with white backing (see 4.2.4).
Table C.1 presents data for 0 :45 geometry. This data has been used to compute equivalent tristimulus
values to those provided in Table 1 and Annex A.