I’m taking a quick break from filming to tell you the best way to watch Mission: Impossible Fallout (or any movie you love) at home. pic.twitter.com/oW2eTm1IUA — Tom Cruise (@TomCruise) December 4, 2018

Anyone who owns a high-definition TV has likely experienced the nagging sensation of something being not quite right when watching films. It's not all in your head. The effect is called video interpolation, or motion smoothing, and last night, Tom Cruise and writer/director Chris McQuarrie dropped a surprise PSA on Twitter (apparently filmed on the set of Top Gun: Maverick) [corrected] to warn us about this evil.

Okay, so motion smoothing isn't actually evil. It's more of a double-edged sword. The feature is great for watching sports, but it makes movies look like "they were shot on high-speed video rather than film," says Cruise. In other words, your Hollywood blockbuster movie will look like a 1970s BBC TV series. That's why it's commonly called "the soap opera effect."

Why does this happen? Essentially, the feature uses image processing algorithms to insert (interpolate) "extra" frames between the actual frames. The TV will process one frame, then another, and then the algorithms will try to guess what a new frame inserted between those two frames should look like. This increases the frame rate to 120fps, to match the HDTV's 120Hz refresh rate. It will smooth out the image and make fast-paced events easier to follow, like basketball games or NASCAR races—or even the nightly news, which isn't meant to look cinematic. But it won't have that "film" feeling anymore: it feels "unnatural," or rather, a bit too real, ruining the illusion.

That's because film is typically shot at 24fps to create motion blur, and most filmmakers exploit that property when designing the cinematography for their films. A notable exception is Director Peter Jackson's controversial decision to film his Hobbit trilogy at 48fps, thereby making it look like the films were shot with the motion smoothing setting turned on.

Usually when celebrities do PSAs, they're talking about social issues, whether it be saving abandoned puppies, disaster relief, the importance of education or diversity, or disease prevention. The fact that Cruise and McQuarrie deemed this issue important enough for a PSA reflects a growing movement in Hollywood to persuade HDTV manufacturers to make it easier for viewers to alter the default settings on their TVs more easily. "If you own a modern HDTV, there's a good chance you're not watching movies the way the filmmakers intended," McQuarrie says. "And your ability to do so is not simple for you to access."

It should be a simple enough matter to change the setting from Sports Mode to Cinema Mode or Movie Mode as needed. But it isn't. Director Rian Johnson tweeted a sample menu last year: “MENU>PICTURE>ADVANCED CONTROLS>REALITY AUGMENTATION>MOTION LIQUIDITY>FLUID FRAME RESTORATION." That is not a simple series of steps. "You want movies to look like liquid diarrhea, fine,” Johnson wrote. “But it should be a choice you make, not a hoop everyone has to jump through to unmake.” And it should be as simple as switching your Instagram filter.

Until that happens, there are several handy online guides for turning off this feature. Sure, you can consult the manual, but Cruise and McQuarrie recommend just typing "turn off motion smoothing [BRAND OF TV]" in your search engine and following the instructions there. This matters because, as Cruise points out, the feature is found on different menus and under different names depending on your brand of TV.

So if you're planning to watch Mission Impossible: Fallout on your home HDTV any time soon, be sure to double-check those default settings. Because Tom Cruise wants you to "enjoy it to the fullest possible effect, just as you would in a theater."

Listing image by via Twitter