The accuracy of a six-color inkjet printing system was tested using object-color spectral datasets known to both span and exceed the system's spectral gamut. The theoretical basis of the system is the Yule-Nielsen modified spectral Neugebauer equation implemented in an iterative
optimization process minimizing spectral RMS error. Results of the end-to-end system based on the reproduction of 170 object colors compiled by Vrhel,
Lawrence A. Taplin, Roy S. Berns, "Spectral Color Reproduction Based on a Six-Color InkJet Output System" in Proc. IS&T 9th Color and Imaging Conf., 2001, pp 209 - 213, https://doi.org/10.2352/CIC.2001.9.1.art00039