Notes. α is the phase angle, Δ is the distance between comet and spacecraft, and “res” the spatial resolution. The time refers to the start time of the first image of an observing sequence. Filters: F22 (649.2 nm, reference), F23 (535.7 nm), F24 (480.7 nm), F16 (360.0 nm), F27 (701.2 nm), F28 (743.7 nm), F41 (882.1 nm), F51 (805.3 nm), F61 (931.9 nm), F71 (989.3 nm), and F15 (269.3 nm). The spectral slope was evaluated in the 535–882 nm range after normalization at 535 nm using the F23 filter image when present, and otherwise an artificial 535 nm image was created from the interpolation of the observations acquired at 480 nm and 649 nm.