Chroma Keying

Hollywood's go-to trick to faking it: chroma keying. The most common form of chroma keying nowadays is the green screen. But this technique dates back to 1940 in Larry Butler's film "The Thief of Baghdad." The same technique hasn't changed much since, and has been a film production staple in all genres.

A green screen is literally just a big cloth in the background in a crazy, unnatural green color. The reason that it's such a crazy green is that neon green is a color does not naturally occur, there for anything else will stand out when it's in front of it. Nowadays, in a video editing program, you can take that footage and select all of the green in the background and delete it. This process is called keying it out. Once it's all gone, you can place an image or video behind that footage to make it look like the subject is in a different setting.


This technique is used during post-production to take a subject from a huge green set to fantasy settings that are impossible to create. This continues to be used today as it the simplest, and cheapest form of set design.

Special Effects Makeup

Makeup is an art that dates back to 6000 years ago. One of the most recognizable historical makeup is that of the ancient Egyptian pharaohs. With organic materials, such as melted beeswax and castor oil, this art form has really come a long way.But as technology advances, makeup has become an endangered species in the movie world.

Makeup by Rick Baker in American Werewolf in London.

In the glory days, back in the 70s and 80s, artists like Rick Baker (makeup artist for Star Wars, Planet of the Apes, and countless other classics) created full characters, who's actors portraying them would wear latex masks and prosthetics glued to their faces for hours; not to mention the amount of time it took to get everything applied.
Special effects makeup is used in film to add to the realism of the visual storytelling.

Watto, Anakin and Shmi Skywalker's slave owner
on Tatooine in Star Wars Episode I: The Phantom
Menace.

In this article, it explains that CGI has "lifted many of the restrictions that were held formerly in place by the limits of make-up, the capabilities of the human body, and physics." That being said, makeup is slowly going away for film, especially science fiction and fantasy. Films like Star Wars, for example. In the 70s, all they had was makeup and puppets. The fact that the jaws and the tusken raiders were actually people in costumes is something that we all naturally overlooked while watching the movies. But when The Phantom Menace was released, that all changed. Characters like Watto, Anakin and Shmi's owner on Tatooine, were made completely through computers, because it was simply impossible to realistically create them with makeup or

puppets. Even JarJar Binks is a computer cartoon. Liam Neeson and Ewan McGregor went running around in a forest talking to an imaginary, clumsy alien that was put into the film during post-production. 

JarJar Binks in Star Wars Episode I: The Phantom Menace.

Greg Nicotero on the set of The Walking Dead.

There are still many shows that use makeup as a primary form of art in their visual storytelling. The Walking Dead  is one of them. The show's head makeup artist, Greg Nicotero, is in charge of creating countless different zombie designs for the show, so that every zombie's wounds and degree of decay tells the story of how they died. 
But even with The Walking Dead, there's still huge amounts of CGI. In episodes like the season 2 finale, massive herds of zombies are nearly impossible to create individually by hand. With CGI, they add several zombies that roam around in the show to fill up the shot, so that the end result is that Rick and the entire crew is absolutely surrounded by walkers. 

Herd of zombies on The Walking Dead.

So we've come to an age that it seems like makeup and CGI go hand in hand. Depending on the physical capabilities of the actors and the effect trying to be conveyed on camera, they are used in film to create a final product that leaves viewers intrigued with the way it looks.

This video goes into the very basics of zombie special effects makeup and how you can make yourself look like one of Nicotero's walkers.

CGI Opens Doors for Limitless Opportunity

So, have you ever wondered, "hey, so what if Avatar and Transformers were made in live-action film"? Well, maybe those movies wouldn't have been as successful if it weren't for computer generated imaging. The invention of CGI was a filmmaking milestone. It opened special effects opportunities that weren't possible before.

In the late-60s and early-70s, computer-generated imaging was at its first steps; creating the grid frame on a radar screen for sci-fi films, such as in Star Wars VI: Return of the Jedi, or James Cameron's Aliens. 

But, over the years CGI evolved, and we are now creating full films using only computer-generated imagery, Pixar's Toy Story (1995) being the first to do so.

Fast forward a decade and now we have films banking on people going to watch them because of their CGI. Transformers for example. So let's go back to the initial question, "what if Transformers didn't have any CGI?"Many would argue that the film wouldn't have been nearly as successful. The film is targeted at an audience that will go to watch it simply because of the realistic, larger than life robots. 

Pyrotechnics

Explosions are an action film staple. Filmmakers continue to use pyrotechnics in production today because it simply looks extravagant and grasps viewers' attention. We continue to see real explosions in film, even well after CGI was invented, because of its authentic effect. Fire is a natural element whose physical characteristics are unpredictable and difficult to mimic with computer graphics. Hollywood chooses to use real, controlled explosions rather than create them in post-production because it's the only way to get a realistic explosion without all the tedious hassle of having to design an unpredictable explosion.
In this video the process of creating a basic explosion in post-production is explained. In the video, the fire was placed over the footage in a editing software called Adobe After Effects. Because this wasn't a real explosion, the flames don't move naturally with the environment the production is set in. The best way to achieve a realistic explosion is to film a small, controlled one in the same environment the production is being filmed in, and then chroma-keying in with the other footage like the guys in Film Riot explained. The process in making a small explosion that can be edited in After Effects can be shown here.

Miniatures

Ever since man began bringing stories to life, there has been some sort of physical art involved. In Shakespearian times, art direction began to play a huge role in his productions. The art in bringing a story to life has evolved throughout centuries, becoming more about catching the viewer's eye, rather than aiding the progression of a plot.

The first special effects in film's recorded history are from the early 1900s was a simple animation of numerous drawing put together in a sequence, titled Humorous Phases of Funny Faces. Films like Metropolis (1927), or A Trip to the Moon (1902), used numerous techniques to create new worlds for their audiences. 
A common technique was to use miniatures, scaled replicas of larger objects, to easily film what they were going for. This is highly evident in the film Attack of the 50 Foot Woman (1958), where a miniature of a city was built to look like the giantess, played by Allison Hayes, was of extreme size. Here in this video, the process of filming with miniatures and their effects are explained.

The purpose of filming with miniatures is to easily film something otherwise nearly impossible to film otherwise, such as the scene in the Death Star trench in George Lucas' Star Wars: A New Hope. Having these unique structures allow for a more visually interesting film and more freedom with story writing, thus attracting viewers.