Chroma Key: Difference between revisions

 

The main methods of controlling the background for live-action shots are, in increasing order of technological sophistication:

The background inserted via Chroma Key can be any visual image. CGI is the most common today, but it can be other live action footage, models, stop motion or cel animation just as easily.

 

 

If any part of an actor or prop is colored the same as the background, that part will disappear. Thus, sometimes the background color is chosen because of the colors to be used in the foreground action. The original run of ''[[Doctor Who]]'', for instance, used green or yellow backgrounds even when blue was the most common color at [[The BBC]], because a large number of its effects shots involved the TARDIS, a timeship that takes the form of a blue police phone box The problem with using yellow was that foreground objects and actors always had a prominent yellow fringe around them. Normally, wardrobe and prop designers simply avoid using greens in the capture range, but this is not always possible; you'll occasionally see bloopers where weather forecasters have part of the meteorology map show up on their ties, for example.

 

It can be fairly tricky to create a viable Chroma-Key effect, especially with amateur equipment—often, it requires fiddling with hue and saturation, and even then, there is often a faint, tell-tale 'border' around the subject where the green-screen footage and the 'real' actor don't match up.

 

== Commercials ==

* Used in Nike's ''[[The Lebrons (advertising)|The Lebrons]]'' commercials for the eponymous family based on LeBron James, as seen in this [http://www.youtube.com/watch?v=6o7kyYZtKxk one].

* As did the film adaptation of ''[[Sin City]]'', in order to re-create all those stylistic comic-book-style angles.

* ''[[Mirror Mask]]'' does the same, in a very ''very'' trippy way.

* The live-action movie of ''[[Speed Racer (film)|Speed Racer]]'' was filmed almost entirely on green screen to give it an anime-style effect.

* The ''[[Star Wars]]'' prequels helped pioneer the idea of minimal set design through Chroma Key.

* [[Tim Burton]]'s ''[[Alice in Wonderland (film)|Alice in Wonderland]]'' used this extensively. The sets seem to consist of nothing but green walls in the proper shape, along with platforms. Only things the human characters touched actually existed on the set, and most seemed to be green and were textured via CG (The Tea Table seemed to be an exception, due to the hatter walking on and knocking stuff off). The staff comments in the "Making Of" stated it was an "Odd Mix" of Full CGI (too many to list), motion capture characters with the actor's head pasted on, normal actors human (mainly Alice), and edited normal actors (the Red Queen and her giant head).

* The body-suit version was memorably used in ''[[Star Trek: First Contact]]'' to erase half of the actress playing the Borg Queen during her entrance-in-two-parts.

* Used a bit in ''[[Who Framed Roger Rabbit?]]'', as you can see [http://www.youtube.com/watch?v=u_VnHAy1Vdc here].

* In ''[[Chitty Chitty Bang Bang]]'', blue screen was obviously used for the [[Flying Car]] scenes. Obvious because [[Special Effects Failure|you can see blue matte lines around the actors in several shots]].

 

== [[Live Action TV]] ==

* ''Drew Carey's Green Screen'' was an improv comedy show that expanded on the green screen antics used on ''[[Whose Line Is It Anyway?|Whose Line Is It Anyway]]''.

* E!'s ''[[The Soup]]'' (and its predecessor ''Talk Soup'') is videotaped entirely in front of a green screen. This led to a particularly memorable incident when a guest wore a pair of Italian flag briefs, which made it appear as if a portion of his pelvis was missing.

** In an interview, [[Jon Pertwee|Pertwee-era]] producer Barry Letts said that while the rest of the world calls it Chroma Key, "[[The BBC]] always insists upon calling it [[Insistent Terminology|'Color Separation Overlay']]".

*** You'll hear this a lot on 70s ''Doctor Who'' DVDs. It's also referred to in an episode of [[Monty Python's Flying Circus]], in a shot where the frame is split between live action and a [[Terry Gilliam]] cartoon.

'''[[John Cleese]]''': Colour Separation, you cottonhead. }}

* ''[[Sanctuary]]'' is shot almost entirely in Chroma Key.

* Used extensively and to great effect (sometimes) in [[Filmation]]'s ''The Ghost Busters'' for the Ghost Dematerializer visual effects.

* The British version of [[MTV 2]] has a flagship show called Gonzo, consisting entirely of host Zane Lowe sat on a brown couch in front of a blue screen. The show is "as live" and therefore no corrections are made when items like guests' clothing match the background and disappear.

* The Irish political debate show "Tonight with Vincent Browne" uses a ridiculously obvious blue screen. It shines on to the faces of guests or, in the case of the host, gives him a [http://www.youtube.com/watch?v=HzVLSn-96tE very strange blue afro.]

* When [[My Name Is Earl|Earl]]'s list item of the week involved a television news anchor, he and Randy went down to the studio. Randy wandered into the green corner, wondering why it was there, when he noticed himself on the monitor, standing in front of a weather map. When he unzipped his jacket to reveal a green shirt, he freaked out, seeing himself as just a floating head and hands. He later figures it out enough to do a [[Pac-Man]] impression.

* ''[[Super Sentai]]'' suffers this in some of the early series, particularly ''[[Dengeki Sentai Changeman]]'' at the end and sporadically throughout ''[[Choushinsei Flashman]]''. By the time ''[[Hikari Sentai Maskman]]'' aired, the production staff no longer use it.

* [[The Angry Joe Show|Angry Joe]] uses it as his background.

* [[The Spoony Experiment|The Spoony One]] will bring it out every once in a while for their skits in reviews.

 

== [[Western Animation]] ==

{{reflist}}

[[Category:Camera Tricks]]