The dithered highlight on the sphere looks odd because it was calculated in a non-linear colorspace. You can get better looking results by converting to a linea

The dithered highlight on the sphere looks odd because it was calculated in a non-linear colorspace. You can get better looking results by converting to a linear colorspace, dithering, then converting back to sRGB. Eg, in ImageMagick, using the same 8x8 matrix: convert Dither2-Exp_crop_resize.png -colorspace RGB -ordered-dither o8x8,2 -colorspace sRGB Dither2-Exp_dithered.png Result: https://imgur.com/a/81bNg https://imgur.com/a/81bNg