It’s one of the most magical moments of watching a movie – the the screen widens and the opening credits roll, the expanding canvas drawing the audience into the fictional world they are about to become immersed in.
Yet there’s a rational, rather than emotional, reason why this always happens before a film: the adverts that the multiplexes show before the film are shot in 16:9, the standard format for TV content, while the film will normally be shot in a wider ratio such as 2.35:1.
Widescreen content works perfectly in a commercial cinema – which has been designed specifically to handle multiple aspect ratios – but having different types of content shot in different widths and heights can be a massive pain when watching films at home. Films shown on a television will usually have black bars (known as mattes) taking up part of the screen in order to fit the entire image comfortably. This process is called letterboxing, and is a major annoyance to cinephiles who want to watch their films in the way the director intended.
Televisions once displayed content in 4:3 ratio (the numbers equate to width:height) although these days they are almost universally designed to 16:9. This rule extends to the new generation of 4K Ultra-HD televisions, as the enhanced resolution – 3840 x 2160 – retains the same aspect ratio as high-definition 1080p content.
To fit wider content onto a modern TV screen without resorting to letterboxing, there are a couple of options, none of which result in a perfect replication of the original content. Zooming or cropping a full-sized image so as to fill the entire screen removes a lot of detail from the sides of a 2.35:1 film, including potentially crucial details. Stretching the content to fit the screen, meanwhile, results in the image becoming noticeably distorted, making characters seem incorrectly proportioned.
Most content shot for television is 16:9, so there will be no problems with watching the football or most programmes (although if you’re watching Netflix shows such as House of Cards or Stranger Things, the 2:1 ratio might result in a small amount of letterboxing).
The main problems with aspect ratio comes when watching films, which have been (and are still being) shot in an incredible array of formats. 2.35:1 is considered as close to a ‘standard’ format as we’re likely to see, although films are also likely to be shot in 2:39:1 or similar.
Older films were usually shot in 4:3, known as Academy ratio, while films dating from the 50s and later frequently use even wider aspect ratios, such as 2:59:1 or even more expansive vistas: Tarantino’s The Hateful Eight is a modern day example of a picture shot using 70mm film, resulting in an ultra-wide 2.76:1 image.
The common solution to this is to use a 2.4:1 projection screen paired with a projector, which allows for widescreen movies to be viewed in all their glory. While almost all projectors offer native support for 16:9 rather than 2.35:1, this is easily overcome by using a zoom lens to resize the content being displayed, or a 1.33x anamorphic lens with electronic scaling to display the image at the appropriate size.
While this is perfect for wider ratios, scaling content for this type of screen height does leave 16:9 content looking markedly smaller than it would normally, and there is still the issue with masking that needs to be overcome. Regardless of whether a projection set-up is designed for 16:9 or 1.35:1 viewing, motorised masking (the same system as that used in a commercial cinema) can ensure that the screen size perfectly fits with the aspect ratio of the content. This system has deep black borders of absorbent material along all four edges of the screen, which move electronically to the desired size and, due to the contrast it provides, increases the dynamic colour range that your eye can make out.
Whether you go for 16:9 or 1.35:1 as the standard for your home is up to you and your household’s needs, but the general rule is that, for TV programmes and video games, 16:9 is the better option, but for watching films a wider screen gives you much more flexibility.
Of course, some films use multiple formats in a single film, such as Christopher Nolan’s The Dark Knight, which employs IMAX ratio (1.43:1) in certain scenes and 2.35:1 throughout the rest of the picture, or Wes Anderson’s The Grand Budapest Hotel, which boasts three separate aspect ratios as a stylistic choice to represent the different eras depicted in the film.
With such a disparity in content size, there will never be a perfect solution – but picking the size that’s right for the content you prefer to watch can keep you from becoming exasperated the next time those dreaded black bars appear.