Here's the scene from Head featuring Peter's song, "Long Title," along with its special solarized color effects.
And now check out this live footage (courtesy of sunnygirlfriend13 on YouTube) from Rama, Ontario, Canada on April 24, 2015. The same solarized effect was utilized during the song, and it was apparently the only time this effect was used during the run of Monkees concerts in 2015. Really cool! Thanks to Melanie Mitchell for taking notice!