You know how, in comics and western animation, they indicate that something is moving really fast by showing it as just a blur, perhaps with contrails?
This is the recording of that phenomenon.
Interestingly, it gets used in live-action film, too. This usually requires special effects, as anything in Real Life that moves fast enough to be seen only as a blur is usually barely seen at all, and that usually isn't what the filmmakers are aiming for.
In the world of CGI, motion blurs have to be faked by a bewildering array of post-processing tricks — your game console effectively burns a lot of processing power adding back in the flaws filmmakers struggle to take out. It's not just cinema-envy, though. Blur does a lot of work ameliorating a low frame rate.
In animation, the effects of motion blur may be shown as either the moving object becoming stretched in the direction it moves (termed "smear") or the moving object being shown multiple times ("multiple"). Some CGI cartoons, especially of the zanier sort, may use a combination of smears, multiples and genuine motion blur. Ninjas who do this are often drawn to be blurry black dots.
- For the chase scenes in the Wallace & Gromit shorts, the camera was attached to whatever vehicle was involved (a toy train, a motorcycle, etc.) and moved along during exposure, resulting in a blurred background - basically a revival of the "Go-motion" technique, as the audio commentary for "A Matter of Loaf and Death" points out.
- In another Stop Motion film, ParaNorman actually went so far as to sculpt these. You heard that right, they sculpted Motion Blurs as replacement faces for the puppets. These were utilized in the facewarping effects of Agatha among other techniques.
- On The LEGO Movie, there are scenes where blurs made of Lego bricks are used for characters moving really fast, such as when Benny the Space Guy builds his spaceship.
- In Turning Red, motion blur is most apparent during the dodgeball scene where Mei throws a dodgeball hard enough to break a window.
- Between 1980 and 1993, "Go Motion" (a process developed by Industrial Light & Magic and Phil Tippett for use in The Empire Strikes Back) was used in a number of films to add motion blur to the subjects of traditional stop-motion animation in order to get a more realistic portrayal of movement. It was eventually abandoned after the advent of computer-generated effects, as it is far more expensive and time-consuming than CGI. (Not completely abandoned; it's used in the Wallace & Gromit shorts, see above).
- An episode of The X-Files involving teenagers that could slow time down for everyone but themselves, had a key plot-point where school security footage was found to show a strange blur. Using experimental technology to colorize it the agents reveal the blur is made up of the school colors, implying that it comes from the jacket of one of the superpowered teens.
- Smallville is a fan of this any time Clark, Kara, or Bart use their superspeed. At one point Jimmy Olsen even caught a picture of Clark in action, but all the picture showed was a red and blue blur, which led to everyone referring to him as The Red-Blue Blur. Later this was shortened to just The Blur. Clark's didn't take the name Superman until the end of the show, so The Blur works fine for him.
- Sometimes averted in sports broadcasts. Cameras with short exposure times per frame produce sharper images for purposes of slow motion and freeze-frame analysis, but look unnatural at normal speed due to the lack of motion blur.
- In Supernatural, ghosts frequently move from one place to another in a blur (often accompanied by a Scare Chord).
- The cover of the January 1934 issue, advertising Donald Wandrei's "Colossus", has a foreground ship with blur and lines indicating that it is moving from the lower right to upper left of the page. In the background, many other ships are shown to be moving in the opposite direction based on the way their lines fade out and the presence of a blob at the forefront of the line.
- The cover of the May 1935 issue, advertising John Russell Fearn's "Earths Mausoleum", has a yellow cigar-shaped rocket with lines and blurring to indicate that it is moving quickly to the tower in the background.
- The cover of the September 1935 issue, advertising John Russell Fearn's "The Blue Infinity", gives motion lines to the earth, implying that it is getting towed through the yellow tunnel by the purple ray, leaving the stars in the background motionless.
- The cover of the October 1935 issue, advertising Nat Schachmer's "I Am Not God", has a Swirly Energy Thingy with motion lines, both behind and in front of the foreground figure in a deep-sea diving suit.
- The cover of the November 1935 issue, advertising Stanley G. Weinbaum's "The Red Peri" and Charles Willard Diffin's Blue Magic, has two rockets shown to be moving in opposite directions by using blur and motion lines going in opposite directions.
- While later video games use motion blur in some form or another to smooth motion between frames, they tend to come into three forms:
- The cheaper method from the old days, used in games like Metal Gear Solid 2: Sons of Liberty and Resident Evil 4, has each frame fade over the next, creating the impression of "afterimages". It's a cheap effect, and as such is mostly used in older games.
- Another method of faking it is the use of 2D cards and filters. In many Sonic The Hedgehog games, Sonic's legs will disappear and be replaced with a card specifically for his fast-moving legs, and when rolled up into a ball in Sonic Adventure the model will have a "blur sphere" that rotates around the character. In many older racing games such as Burnout, a blur filter would be applied to the edges of the screen to emulate the effect of objects whooshing past the camera.
- The more expensive method, used in Crysis and most current-gen games, models the exposure time of an actual camera. This looks both smoother and far closer to the feeling of "motion" seen in the trope picture, as it can be done in real-time to everything on-screen, rather than needing to be done manually for specific situations.
- Extremely common in first-person console games. Using a mouse, it's possible to turn extremely quickly (especially with more expensive mice that allow sensitivity to be adjusted on the fly). Using an analogue stick on a controller can only turn at a fixed maximum rate, which is usually quite slow to allow fine movement rather than wildly spinning every time the stick is touched. Games frequently apply motion blur to give the impression turning is much faster than it actually is.
- Conker's Bad Fur Day: A cutscene preceding the boss battle against The Experiment uses this effect, to show in slow-motion that Conker's attempt to grab the Little Girl after defeating some incoming submarines is a bad idea (Rodent shouts a Big "NO!" as he tries to do this, knowing the Girl's true identity).
- Sonic The Hedgehog can do this. In some of the 3D games, Sonic can create a blur by Spin Dashing. In fact, everyone who can use the Homing Attack has their own Motion Blur similar to Sword Lines.
- Gamespite has an interesting discussion of how Street Fighter III's Makoto is animated so as to suggest more movement than there are animation frames. Check out some examples here.
- Games with limited animation tend to blur fast moving body parts in addition to applying speed lines. When a blurred character or body part remains slow enough for the player to control the effect is quite surreal.
- Crysis implemented a motion blur system that applied the effect to individual moving objects instead of simply the entire scene as the player moved the mouse around. With config file tweaking, the full-screen motion blur could be turned off while leaving the per-object motion blur on.
- The Legend of Zelda: Majora's Mask uses motion blur in great amounts, usually in cutscenes but sometimes in real-time gameplay. And this is on the Nintendo 64. Granted, the game was released in 2000 and uses the 4 MB RAM expansion pack, but the use of motion blur in real-time is still quite amazing for a mid-90s console. The motion blur makes a brief return in The Legend of Zelda: The Wind Waker (as a visual effect when Link is hit by an explosion or repeled by the energy barrier surrounding Hyrule Castle) and The Legend of Zelda: Twilight Princess (in a few select cutscenes, such as during Colin's kidnapping by King Bulblin or when a boss appears), but later games omitted it altogether.
- MechWarrior Living Legends, being a Crysis Wars mod, carries over Crysis's amazing motion blur system, though it's disabled by default for the sake of performance. Early versions of Mechwarrior Online had sickening amounts of motion blur, which were toned down in later patches.
- My "Dear" Boss: The boss tends to be blurry if he flies fast enough.
- Star Fox Adventures: This effect is used briefly during Fox's teleportation between locations via the Warpstone, and more dramatically during the Test of Fear in Lightfoot Village.
- The Fox Sister uses motion blur in some action sequences.
- The various animated appearances of the Flash from the DC Universe have used this to suggest his super-speed.
- Done with Superman from time to time too, especially in Superman: The Animated Series.
- Quicksilver, another speedster from the Marvel Universe, uses motion blur in the same way.
- In Looney Tunes the quick characters are portrayed this way:
- Road Runner;
- Speedy Gonzales;
- Anyone who needed to leave/arrive in a hurry, really.
- The Chuck Jones Merrie Melodies short "The Dover Boys" pioneered the use of the smear, in which the characters appear elongated for two or three frames as they zip from one pose to the next. The technique has been used by animators ever since, most notably on Johnny Bravo. Here is a Tumblr blog dedicated to smears and similar tricks.
- Ninjago: This became common when the show switched to WildBrain for its animation, using a 3D animated version of this trope. For example, the Prime Empire short "Let's Dance!" utilizes "motion blur" to show the dance instructor moving quickly around and room and into different poses as well as Nya and Jay spinning around, In fact, Nya appears twice in many frames at one point.
- Early in the history of The Simpsons, there were frequent spears and multiples, such as Maggie falling off a tree branch◊ in "Good Night", Lisa turning to read a dictionary◊ in "Bart the Genius", and Homer being elbowed by Marge◊ in "Bart the General". Since the creators preferred more naturalistic animation, this all but vanished, but it still comes on occasion, like Homer's shoelaces getting caught in an escalator◊ in "The Wandering Juvie", Lisa realizing she needs to finish her social studies project◊ in "Little Girl in the Big Ten", and Homer spinning into a locker◊ in "Father Knows Worst".