The Medford Public Library welcomes Boston sports photographer Steve Babineau to discuss his latest book, “Behind the Lens.” Babineau, the team photographer of the Boston Bruins, has been photographing big-league sports events for 50 years. “Behind the Lens” is a lovingly curated collection documenting both his earliest published (and unseen) works, and the wild emergence of the unforgettable World Hockey Association (1972-1979). Join Babineau for a look back at the timeless legends who were finally getting paid, the journeymen who finally got a shot at the pros, the 17-year-old who would go on to rewrite record books, the brawls and goals, the glorious ’staches and flows, the highs and the lows of the WHA.