In an age of music videos whose rate of viral spread eclipses that of any other music format, the 1985 video for a-ha’s immortal synth-pop hit “Take on Me” endures as one of the classics of the genre. As new generations discover the greatness of a-ha, photographer Just Loomis, who shot the cover images for five a-ha albums, and who has been documenting the band since the glory days of “Take on Me,” publishes his superb collection of never-before-seen a-ha photographs.