A method forms a pattern of metallic nanofeatures that generates by plasmonic resonance a desired image having a distribution of colors. The method includes providing a substrate having a layer of photosensitive material, exposing the layer to a high-resolution periodic pattern of dose distribution, and determining a low-resolution pattern of dose distribution such that the sum of the low-resolution pattern and the high-resolution periodic pattern of dose distribution is suitable for forming the pattern of metallic nanofeatures. The lateral dimensions of the metallic nano-features have a spatial variation across the pattern that corresponds to the distribution of colors in the desired image. The layer of photosensitive material is exposed to the low-resolution pattern of dose distribution. The layer of photosensitive material is developed to produce a pattern of nanostructures in the developed photosensitive material. The pattern of nanostructures is processed so that the pattern of metallic nanofeatures is formed.