The iridescence effect, produced by structural color, is difficult (if not impossible) to capture and print using traditional CMYK pigments. RGB pigments, nonetheless, generate structural colors by light interference. The layered surface structure generated by pigments’ particles reflects different wavelengths of light in different viewing angles. In printed media, pigments’ particles will collectively influence the optical response of the surface, depending on their size, orientation, structure, and dimensions, ultimately, affecting the visual characteristics of the image perceived by the observer. In this work, we have studied the influence of different halftones’ structures on printed images, produced with RGB inks via screen printing. We investigated the influence of different halftones’ structures in creating different spatial combinations of inks on the printed surface that reproduce the characteristics of iridescent effect of a headdress made of quetzal feathers. We applied first-order, second-order, and structure-aware FM halftones to compare how they influence the reproduction of the material qualities of the object represented in the image. The results show that the structure-ware halftones improve the representation of the image structures and details and, therefore, it could better convey the 3D surface features that produce iridescence effect in the original feathers of the headdress.
Fereshteh Abedini, Abigail Trujillo-Vazquez, Sasan Gooran, Susanne Klein, "Effect of halftones on printing iridescent colors" in Electronic Imaging, 2023, pp 206-1 - 206-6, https://doi.org/10.2352/EI.2023.35.15.COLOR-206