The purpose of commercial post production can vary in any film, advert, or other production, but the essential aim is the same: to ensure that what is initially filmed by whatever means is adjusted as required to transform it into the final product intended to be seen by viewers.
In many cases, this can simply be about cleaning up the sound so that background noise is eliminated, or perhaps cutting out parts of footage that are not useful or contain errors. Blurs can be eliminated and light levels adjusted to improve the visual spectacle.
Cutting out clear errors can prevent the repeat of famous cinematic errors, such as the chariot race competitor wearing a wristwatch in the 1960s swords and sandals epic Ben-Hur (although the alleged red sports car in the background was an urban myth, according to lead actor Charlton Heston).
Low Tech Or CGI?
In other films, post production is more complex and high-tech, such as when original shoots have involved a green screen and action is added, either the animation technology of the kind used in the early Star Wars films or the CGI seen in ever-increasing detail since the 1990s. Titanic was a notable example of the latter.
However, some genres of films will require very different types of post production, because the kind and levels of technology used in making them vary enormously. A prime case in point is that of the zombie movie, a theme much in the news after 28 Years Later recently hit the cinema screens.
While older zombie films like Night of the Living Dead relied on costumes and makeup (as, to a large extent, did more modern flicks like 28 Days Later, which invented the idea of running zombies that could catch, chase and kill people), others went big on CGI. World War Z was a classic case of the latter approach.
Others had to make adjustments due to the total absence of CGI. Keen viewers can see a deleted scene on the DVD of 28 Days Later of wrecked cars on a motorway, but, because CGI was not used in post-production to remove it, moving traffic is visible in the background. For this reason, the scene was cut.
How IPhones Helped Make 28 Years Later
The film had its first sequel in the form of 28 Weeks Later in 2007, while the long-awaited 28 Years Later has just been released. The latter film highlights how some very different approaches can be combined in filming, requiring different post-production techniques.
Most notably, the use of the iPhone Pro Max – 20, in fact – provided a different approach to filming. This was not as low-tech as previous films shot using home video cameras of the sort used in The Blair Witch Project or Children of Men.
Director Danny Boyle’s reasoning for using the cameras was that while a real apocalyptic situation in the 2000s when 28 Days Later came out would have been shot on home video cameras, if it happened today, footage would come from Smartphones.
Needless to say, one imperative for post-production is that nothing is done that takes away this effect, as that would defeat the object of the exercise.
Of course, the increasing quality of cameras means an iPhone now offers an exceptional level of picture technology. This, in turn, highlights a simple fact: Even without high-tech special effects like CGI, the nature of post-production work remains varied due to the array of different tools used in initial shooting.