While attentively watching a film, how often have we questioned ourselves why a certain area within the frame is kept out of focus, yet doesn’t distract us from the story? Consciously, we don’t because the cinematographer has maintained a balance in the relationship between the spatiality and perspective within the frame. He has achieved it with a technique known as the depth of field. So what exactly is ‘depth of field’? An optical term used in film and photography, it’s simply the distance between the closest and the farthest object in an image that are in apparent sharp focus.
Late American cinematographer Gregg Wesley Toland, A.S.C. has been credited with pioneering the deep focus technique in world cinema. He used it for the first time in John Ford’s family drama The Long Voyage (1940). A year later, he utilized the technique to its full creative potential with Orson Welles’ masterpiece Citizen Kane.
The relevance of depth of field is used to determine the range of visible sharpness in front of the lens within which objects appear in focus to the human eye. If objects are too close to the camera or beyond the far end of that range, the image will appear blurry and out of focus.
What is depth of field in photography?
To understand the concept better, let’s understand depth of field in photography. In photography depth of field is the region within the image that is relatively sharp and in focus. It helps the photographer to determine the particular areas in the photos they want in focus. There are two types of depth of fields:
Shallow: A shallow depth of field captures a narrow range in which objects appear in focus. It is appropriate for focusing on a subject that is closer to the camera. This technique also helps in the process of macro photography, where very small subjects are captured in a larger-than-life-size. For example, a close-up of dewdrops over a leaf would require a shallow depth of field.
Deep: A deep depth of field captures a long range in which objects appear in focus. It is appropriate for focusing on a subject away from the camera. For example, the long shot of the sun rising at the far end of the horizon.
Why is depth of field important?
One of the key factors of a beautifully composed image depends on the nature of focus on the primary subject within the frame. Let us say we have to capture the close-up of a character but the background is not impressive at all. Or the filmmaker wants to keep the background out of focus so that he/she can infuse the character with psychological depth. In this case, creating a shallow depth of field would heighten the aesthetic appeal of the image.
In Paul Thomas Anderson’s The Master (2012) the use of shallow focus helps the viewer empathize with the bizarre persona of Freddie Quell, played by Joaquin Phoenix.
Take for another instance where we have an amazing view of a landscape where in the background there is a mountain, in the midground a dense forest and in the foreground, cattle grazing on the field. To capture the beauty of all the three creations of nature, a deep depth of field will be a perfect choice. Filmmakers have been using the technique for scenes that involve activities in both the foreground and the background of the frame. The staging of such a scene involves the placement of actors, props, and set pieces at great depth. A deep focus strategy enables the filmmaker to capture the scene with sharpness and clearness and lucidity as well as impregnating the frame with details.
In The Hateful Eight (2015), Quentin Tarantino uses deep depth of field to utilize the cinematic idiom of spaghetti Westerns.
So, controlling the amount of depth of field within the frame makes it possible to emphasize certain parts and de-emphasize other parts.
What is Bokeh?
Bokeh is a Japanese word that means ‘haze’ or ‘blur’. In recent times it is considered to be a popular photography method that utilizes depth of field. Bokeh is achieved by using the technique of shallow focus, where blurring the background of an image creates a pleasing effect. It is believed that Mike Johnston, a photographer, first used the term in an article that appeared in Photo Techniques magazine in 1997.
Examples of depth of field in films:
1. The Searchers (1956)
In this scene from John Fords’ The Searchers, Debbie Edwards (Natalie Wood) informs her brothers, Ethan Edwards (John Wayne) and Martin Pawley (Jeffrey Hunter), that she has become a Comanche and wishes to remain with them. But Ethan would rather see her dead than living as an Indian. As he tries to shoot her, Martin shields Debbie. But a Comanche wounds Ethan with an arrow and what follows next is a powerful action sequence. As Ethan and Martin race their horses from the creek area and down along a long incline, a dozen or more Comanches come tearing after them. Ethan and Martin swing past a huge outcrop of rock and go tearing along a vaulting wall of stone as bullets whine and ricochet.
Cinematographer Winton C. Hoch has shot the scene from every possible angle to explore the deep depth of the vast landscape. The untamed frontier, open landscape of mountain ranges, rugged lands, and vast plains has been beautifully integrated with the chase and gunfight using the deep focus of the depth of field.
2. The Hero (Bengali, 1966)
A famous actor of Bengali films, Arindam Mukherjee (Uttam Kumar) and Aditi Sengupta (Sharmila Tagore), a young journalist, are dining in the pantry car of the train. As the train stops on one of the platforms, fans throng the window to get a glimpse of their matinee idol. Aditi is visibly embarrassed as she tries to avoid a scandal. But Arindam enjoys the attention and tells Aditi to behave casually.
Throughout the scene, Satyajit Ray and his cameraman Subrata Mitra keep the enthusiast public in focus using deep depth of field. The characters neither in the background nor in the foreground are out of focus. The scene symbolically implies that the fame and wealth earned by Arindam by entertaining these people have now become an indispensable part of his identity. Without the fan following, Arindam’s reputation will be in shreds. And whoever comes close to Arindam will also garner attention, like Aditi in this scene.
3. Fargo (1996)
Marge (Frances McDormand) takes slow, gingerly steps down the slope, through the deep snow. She moves from tree to tree, as the roar grows louder. Grimsrud (Peter Stormare) is laboring over a large power tool that his body blocks from view. Marge slogs down to the next tree, visibly disgusted. She discovers that Grimsrud is feeding his partner’s dismembered body into a wood chipper. As Grimsrud forces more of the leg into the machine he realizes that his demonic act has been unearthed. He is startled and hurls a small log at Marge before attempting to flee. But Marge shoots him in the leg.
Roger Deakins’ sweeping visuals elevate the story, evoking fear and escalating tension. The setting of the harsh winter season reinforces the macabre behaviour of the character. The vast snowy-white landscape of Minnesota and North Dakota, captured with a deep depth of field, brings the feel of a snowbound film noir.
4. The Social Network (2010)
Mark Zuckerberg (Jesse Eisenberg) and Erica Albright (Rooney Mara) are on a date in a bar at the beginning of David Fincher’s Academy-winning The Social Network. Both are engaged in a formal conversation. Mark expresses his discontentment with the prejudices of the system. He’s bitter about the fact that despite being talented he’d never be invited to join the Harvard elite. Soon, the scathing conversation becomes personal. Erica can no longer take Mark’s bragging. She leaves him for good. The scene enables the viewers to understand the motivations and intentions of our protagonist.
Cinematographer Jeff Cronenweth frames both the characters with a shallow depth of field to create a layered character study of two strong figures engaged in a skirmish. It is a well-crafted scene where the three departments of filmmaking — script, edit, and the camera, working in tandem to fulfill the vision of the director.
5. Her (2013)
Theodore Twombly (Joaquin Phoenix) in Spike Jonze’s Her is going through a divorce with his wife Catherine Klausen (Rooney Mara). To overcome the pangs of separation, he purchases an operating system upgrade that includes a virtual assistant with artificial intelligence. The AI is designed to promise an intuitive entity in its own right and he chooses a female voice. He is pleased to get introduced to Samantha, a friendly female voice, by Scarlett Johansson. The AI learns and adapts Theodore‘s conscience and emotions quickly. Theodore strikes an emotional chord with the voice in no time.
Dutch-Swedish cinematographer Hoyte van Hoytema frames Theodore with a shallow depth of field so that he can present the viewers with a character who is a futuristic individual. Theodore is the kind of guy who is enveloped and pervaded by technology. The blurred background is symbolic of the false semblance of a relationship that exists only in a virtual world.
6. Loveless (Russian, 2017)
In Andrey Zvyagintsev’s Oscar-Nominated Loveless, the moment Zhenya (Maryana Spivak) realizes that her only son Alyosha (Matvei Novikov), has been missing, she immediately calls her husband Boris (Aleksey Rozin). The couple is about to undergo an divorce, so there’s already bitterness and a grudge against one another. The tragic incident of Alyosha acts like fuel to the fire. As Zhenya and Boris talk over the phone, each of them tries to send the other on a guilt trip.
Cinematographer Mikhail Krichman frames both the characters in a shallow depth of field to emphasize that both the father and mother are responsible for the fate of their innocent son. They were so engrossed with their personal life and state of affairs, that they overlooked his emotional turmoil. This is a crucial scene as it sets forward a chain of events that depict the sharply delineated tale of the corruption of human emotions in a woeful procedure.
7. Vice (2019)
In Adam McKay’s Vice, Dick Cheney (Christian Bale) is a sharp and astute politician, who knows how to take advantage of opportunities and reshape the office of the Vice President under the administration of George W. Bush. In this particular scene, Cheney convinces W Bush to offer him the mandate of managing the bureaucracy, overseeing the military, energy, and foreign policy. A little bit of flattering also goes in the way of achieving his goal. He massages Bush’s ego by describing him as a kinetic leader, who makes decisions based on instinct, a quality that senior Bush lacked. With this, Cheney has won the confidence of junior Bush and treads his way into an important chapter of American political history.
Cinematographer Greig Fraser frames both the characters in a shallow depth of field to delve into the psychological game played by Cheney to manipulate Bush with caution.
Tips for working with depth of field – How to achieve it
Several factors affect depth-of-field in cinematography and one can achieve it by applying the following camera adjustments:
Focal Length of the lens: A focal point is the film plane that the cameraperson wants to keep in focus when the lens is focused at infinity. It is that area of an image where the subject is within the perfect point of focus. And focal length is the distance from the optical center of a lens to the focal point. So, shorter the focal length, the greater the depth-of-field in the image. Whereas, lenses with longer focal length, helps to create a shallow depth effect in close-up shots.
Aperture of the lens: In the middle of a camera lens there is a small hole or window that allows light to pass onto a digital camera’s image sensor or the film strip on a film camera. The aperture of a lens is usually an adjustable iris (or diaphragm) that limits the amount of light passing through a lens. A small aperture allows less light to reach the sensor, which helps create a longer depth of field. When the aperture is large more light reaches the sensor and it becomes easier to create a shallow depth of field. To achieve a large or deep depth of field, a smaller aperture is required.
Camera Sensors: It is worthy to keep in mind that cameras with smaller sensors have larger depths of field because they allow for shorter focal lengths. Whereas, larger formats, like 35mm or Imax, have less depth-of-field than smaller formats like 16mm or most video sensors.
How to achieve depth of field on your smartphone camera
The image sensor in a smartphone is tiny in comparison to the regular and professional camera. So, to achieve the depth of field on a smartphone camera, here’s what you can do:
1. On your camera app, swipe to portrait mode. Move closer to the subject.
2. Lock the subject by touching the screen unless the AE/AF lock sign appears. AE/AF means the exposure and focus have been locked.
3. Adjust the brightness according to one’s aesthetic choice.
4. Finally hit the shutter. One should hold the smartphone steadily or consider using a tripod.
There are three other options to achieve the desired results:
1. Using a third-party application such as Protake – Mobile Cinema Camera, which allows shooting in shallow depth-of-field videos. This application has a Lidar sensor and helps to attain the preferred result. However, the application has the limitation of working only at 1080p and doesn’t support image stabilization. Even the manual exposure control is not applicable.
2. Using the Ulanzi DOF Adapter.
3. Buying an iPhone starting with 7 Plus and iOS 10.1 and above which can capture photos with depth of field similar to a DSLR.
Maintaining focus within a shot is one of the most important aspects of cinematography. This is a specialized job assigned to a key member of the camera department in film and television production known as a focus puller. Concentration, precision and a keen eye for distances are the qualities required for this highly skilled profession. If a shot is discovered out of focus during the post production, no amount of hard work or a miracle can alter the fate of the shot.