Photography is best known as capturing a specific moment in a spilt second
to freeze time and reveal what the naked eye cannot see. Digital photography
can also be used to explore the passage of time with time-lapse and stop
motion photography, video, and sound.
Time-lapse Photography
Photography is used for a variety of purposes: to record a dramatic sunset, chronicle the human condition, or focus on the personal. Additionally, still photography can also reveal what we simply cannot see—from the grandeur of outer space, to the incredible detail of macro photography, to the unseen passage of time that we are all a part of. Time-lapse photography captures slices of time that you then render as a movie file to speed up the passage of time. Time-lapse photography has come a long way since we were in third grade when the teacher showed the class scratchy, flickering movies of crocuses breaking through the soil. It was fascinating to see how the plants twisted and turned, and pale stems were transformed into full blossoms. That is the magic of time-lapse photography in which a series of photographs of the same scene, taken at regular intervals over a period of time, are assembled together and then played back as a movie file. By photographing a changing scene in regular intervals over an extended period of time, you are capturing the subtle changes of light, shadow, motion, and metamorphosis that the naked eye simply cannot see. Suitable subjects you can use to start learning about time-lapse photography include sunrises and sunsets, landscapes with moving cloudscapes passing through the sky, incoming and outgoing tides, urban scenes, construction projects, and of course blossoming flowers.
The equipment
The equipment to do time-lapse photography ranges from point and shoot cameras to (as we recommend) a DSLR with a sturdy tripod and an intervalometer , which is a sophisticated cable release that controls the intervals between frames, the number of frames, and even when the camera should start to take pictures. Some cameras include an intervalometer function. To shoot for extended periods of time or longer than your camera battery can last, you’ll also need an external power supply for the camera. After shooting the source images you’ll need (for the budgetminded) QuickTime Pro, Photoshop CS4, or Photoshop CS5 Extended, or (for the sophisticated high-end) Adobe After Effects or Apple Final Cut Pro to create the image sequence.
How many frames?
For a normal representation of motion, movies are shown at either 24 or 30(really 29.97) frames per second. To create slow-motion effects, you need to play back more frames per second; for example, 60 fps will result in smooth slow motion. To create a more compressed version of time—for example, an entire sunset elapsing in a very short amount of time—you need to play back fewer frames per second. Start by deciding how long the movie should be and then decide on a playback rate based on whether you want slow motion or a faster, compressed representation of time and motion in the scene. Let’s say you want a oneminute movie; use this formula, 60 seconds x 24 frames = 1440 frames. Now you need to figure out the duration of the event. For example, when photographing sunsets, start photographing an hour before sunset and shoot until one hour after sunset. So the actual event in this case is 120 minutes or 7200 seconds. To calculate what interval to shoot at, divide the number of seconds by the number of frames. In this example, 7200 seconds/1440 frames = 5 second intervals. If you want a smoother playback, shoot more frames. For the smoothest transitions, shoot one frame per second. Keep in mind that you can always decide to not use frames that you’ve shot versus needing frames you never captured.
Take these tips to the bank!
Shooting source images for time-lapse photography can be time-consuming
and tedious, so it is best to practice shooting before traveling to an exotic location
to photograph a once-in-a-lifetime event or scene. Consider the following
tips we’ve already learned. We’ve made the mistakes so you don’t have to:
• Clean the camera sensor before a shoot, especially when shooting skies!
• Turn off the LCD preview to extend battery life.
• Use the largest camera card media possible.
• Prefocus the camera in manual focus.
• Shoot RAW to have more control over color balance and exposure
adjustments.
• Shoot JPEG files when learning and to speed up post-shoot workflow.
• If you’re shooting in daytime exteriors or interior scenes with fixed lighting,
use manual exposure. However, if you’re shooting from dawn into
daylight or day into dusk, select an automatic or program exposure mode.
• When shooting late afternoon into nighttime, be sure to use a medium
ISO and a fairly wide-open lens aperture. Otherwise, you could wind up
with exposure times that are slower than the duration between each shot.
• Beware of shooting into the sun for extended periods of time during
sunrise or sunset because the lens can focus the sun’s rays into the body
of the camera and burn pinpoints into the shutter curtain.
Stop Motion Animation
In addition to time-lapse animation, DSLRs work quite well for creating stop motion animated stories. Stop motion animation is a slow and deliberate process that refers to carefully moving elements in a scene, stopping to record a frame, moving the elements slightly again, stopping to record another frame, and repeating the process over and over until you have a sequence of motion created by many photos. This very old animation method has been around almost as long as movies. Many classic monster and fantasy films, such as the original King Kong (1933) and Ray Harryhausen’s Jason and the Argonauts (1963) were filmed this way using motion picture film. Today, DSLRs have been used to create stop motion animation for such films as The Corpse Bride (2005), The Fantastic Mr. Fox (2010), and the Wallace and Gromit and Shaun the Sheep series of animated shorts from director Nick Park.
DSLR Video
The primary choice between making a movie versus a still image is determined by the action. Imagine a photograph of a beautiful landscape. Now imagine that same scene shot with video. Hold it—hold it—hold it; if nothing happens in about 20 seconds, you’ll click onto a different Web site or flip the channel. But if a character walks into the frame or if the frame pans as industrial sounds increase, the viewer will be intrigued and will continue watching. Of course, the photographer could shoot a series of images with captions that address the environmental or social issues that this scene shows, but the videographer will engage the viewer by using a much different set of tools and skills to extend the story beyond the static frame of the still image. Generally speaking, photographers have been primarily concerned with a single frame leading to a final print of the moment that uniquely captures and freezes the light, scene, and subject in a fraction of a second. Videographers and filmmakers concentrate on telling a story through the passage of time.
A photographer is trained to respond and capture “the decisive moment,” whereas a filmmaker uses time, motion, and sound to set the scene, introduce the characters, and develop the story with a beginning, middle, and end. The design, nomenclature, and ergonomics of a DSLR remain rooted in the photographic experience of the past. Until most recently, people used a DSLR for photography and a camcorder for video. Today, photographers are intrigued with the ability to shoot video, and videographers are enamored with the ability to capture quality still images—both with the same camera and lenses. The capabilities of a DSLR as a video camera are so impressive that filmmakers are exploring their use in feature films and in HD broadcasts. The earliest results are very impressive because the fast and sharp DSLR optics allow for working in low light and with a shallow depth of field. The relative compact design and the high quality of the DSLRs allow for unusual camera perspectives that working with cumbersome video equipment simply does not. DSLR cameras have every component and are often better than those included in a modern, professional video camera. In fact, the image sensor on many DSLRs is substantially bigger than those used in most digital camcorders. Speaking naively, all the camera makers had to do to make a still camera into a video camera was add high frame-rate capture; build in the suitable frame buffer and codec support for video file compression; and take advantage of larger and faster storage.
Technical considerations
Working in video is more than changing the camera from single frame to video capture. The technical requirements of a video production are based on the fact that in a movie, either the subject is moving through the frame or the camera is moving, or in some cases as the director Spike Lee loves to do, both are moving. In every instance, stabilizing the camera so the image does not jump and jitter improves the effectiveness and viewer’s enjoyment of the movie. To capture a stabile video, a video tripod with a fluid head that allows you to smoothly pan or tilt the camera without shakiness is an essential piece of equipment. Fluid heads use hydraulic dampeners to make all camera movements as smooth as possible.
To move through a scene, skilled videographers use a SteadyCam support, which looks like a medieval torture harness that the camera is attached to and the videographer wears, allowing the camera to glide through a scene. Interesting to us is that much of the technology that went into the development of image stabilization for video has been miniaturized and adapted into the image stabilization lens that still photographers now rely on to get a steady shot. Sound quality is a critical issue to consider. In fact, viewers are more likely to watch a video with poor image quality but will have zero patience for poor sound. Currently, the microphones built into DSLRs are unsuitable for high-quality sound capture, because they pick up general ambient noise, including your breathing. To capture quality sound, specialized off-camera microphones that can be placed and focused are essential. Using a directional off-camera microphone immediately improves sound quality by being isolated from the ambient noise of the scene, camera, and crew. This is an issue that is solved in feature-film productions by using an entirely separate audio system and a highly trained team of audio technicians. Even with the expertise and staff, location sound is usually augmented or replaced by audio recorded in sound studios. For the occasional moviemaker, we recommend shooting the scene without sound (or removing the sound in post) and adding effective music or narration as the audio track. Working in New York City has allowed Katrin to stumble upon numerous television and movie productions, and she can attest to the fact that nothing is as it appears in the movies or the TV series Law & Order.
The red-blue flicker of police cars are created with rotating gelled lights positioned far away from the action; interior shots are lit with three-story high cranes, scrims, flood lights, and full-on generator trucks; and daylight rarely is, well, just daylight. There are a number of challenges in lighting for action. For a scene to be lit effectively, it must allow the actor to move through the scene with the expected exposure throughout the entire scene without changing camera exposure. Simply put, video requires using more lights with more planning. The more complex the story, the more you have to prepare. The inherent cost of shooting a film prohibits spontaneity. The scene is staged, the interior is set with props, and the actors are rehearsed. The magic is in the hard work; the devil is in the details.
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