Learning cinematography online for free is attainable with the right resources and dedication. Start with YouTube, a treasure trove of tutorials covering basics like camera angles, lighting, and shot composition. Channels like Film Riot and DSLRguide offer valuable insights. Websites such as No Film School and Filmmaker IQ provide a wealth of free articles and forums. For structured learning, websites like Coursera and edX offer free courses in cinematography and film production. Lastly, actively watch films with a critical eye, analyzing cinematographic techniques. Remember, practice is key in mastering the art of cinematography.