High Dynamic Range refers to a wider range of brightness, contrast, and color that can be applied to the movie/TV content during post production, usually by the colorist after consulting with the cinematographer. In recent years, both cinema screens as well as televisions have the ability to display this enhanced imagery. So to take advantage of that better display capability, the post production industry now has technology and tools to create this new enhanced version of the movies and TV shows. Next time you watch a movie, watch the end credits and look for the person who did the Digital Intermediate. That's just a fancy way of saying colorist, and it is becoming common for that person to acquire skills and knowledge about High Dynamic Range.
Let's talk about audio now. Over the past few decades, movies and TV shows were commonly created with surround sound audio, meaning 5.1. The 5.1 refers to speaker layout, specifically for speaker locations in Left, Center, Right, Left Rear, and Right Rear (that's the 5), along with a subwoofer (that's the .1). And sound mixers would therefore make creative decisions based on which sounds they wanted to send to which speaker. But with the emergence of what's known as immersive audio (e.g., Dolby Atmos), sound mixers now have new creative tools to send sounds literally anywhere in the room, without worrying about which or how many speakers there are. Picture a tennis ball that you can hang anywhere in the room. And now think of a sound (e.g., a helicopter) instead of a tennis ball. Sound mixers now have new creative freedom in mixing movies and TV shows. Of course, on the playback side (cinemas or consumer devices), there must also exist the corresponding technology to receive this new type of audio file and play it back as the mixer intended, no matter what the speaker layout is (or even via sound bars or other consumer devices). Fortunately, this playback capability is becoming very common in cinemas and consumer devices. So for a sound mixer, learning this enhanced mixing technique is going to be critical for the future of sound in movies and TV shows.
For both HDR and immersive audio, there are already thousands of movies and television episodes created in these new formats. It's the next wave of premium experience for content, so aspiring film makers, colorists, cinematographers, and sound mixers should become educated about all this.