In photography, shutter speed or exposure time is the length of time that the film or digital sensor inside the camera is exposed to light (that is, when the camera's shutter is open) when taking a photograph. [1] The amount of light that reaches the film or image sensor is proportional to the exposure time. 1⁄500 of a second will let half as much light in as 1⁄250.
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The camera's shutter speed, the lens's aperture or f-stop, and the scene's luminance together determine the amount of light that reaches the film or sensor (the exposure). Exposure value (EV) is a quantity that accounts for the shutter speed and the f-number. Once the sensitivity to light of the recording surface (either film or sensor) is set in numbers expressed in "ISOs" (e.g. 200 ISO, 400 ISO), the light emitted by the scene photographed can be controlled through aperture and shutter-speed to match the film or sensor sensitivity to light. This will achieve a good exposure when all the details of the scene are legible on the photograph. Too much light let into the camera results in an overly pale image (or "over-exposure") while too little light will result in an overly dark image (or "under-exposure").[ citation needed ]
Multiple combinations of shutter speed and f-number can give the same exposure value (E.V.). According to exposure value formula, doubling the exposure time doubles the amount of light (subtracts 1 EV). Reducing the aperture size at multiples of one over the square root of two lets half as much light into the camera, usually at a predefined scale of f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, and so on. For example, f/8 lets four times more light into the camera as f/16 does. A shutter speed of 1⁄50 s with an f/4 aperture gives the same exposure value as a 1⁄100 s shutter speed with an f/2.8 aperture, and also the same exposure value as a 1⁄200 s shutter speed with an f/2 aperture, or 1⁄25 s at f/5.6.[ citation needed ]
In addition to its effect on exposure, the shutter speed changes the way movement appears in photographs. Very short shutter speeds can be used to freeze fast-moving subjects, for example at sporting events. Very long shutter speeds are used to intentionally blur a moving subject for effect. [2] Short exposure times are sometimes called "fast", and long exposure times "slow".[ citation needed ]
Adjustments to the aperture need to be compensated by changes of the shutter speed to keep the same (right) exposure.
In early days of photography, available shutter speeds were not standardized, though a typical sequence might have been 1⁄10 s, 1⁄25 s, 1⁄50 s, 1⁄100 s, 1⁄200 s and 1⁄500 s; neither were apertures or film sensitivity (at least 3 different national standards existed). Soon this problem resulted in a solution consisting in the adoption of a standardized way of choosing aperture so that each major step exactly doubled or halved the amount of light entering the camera (f/2.8, f/4, f/5.6, f/8, f/11, f/16, etc.), a standardized 2:1 scale was adopted for shutter speed so that opening one aperture stop and reducing the amount of time of the shutter speed by one step resulted in the identical exposure. The agreed standards for shutter speeds are: 1⁄1000 s; 1⁄500 s; 1⁄250 s; 1⁄125 s; 1⁄60 s; 1⁄30 s; 1⁄15 s; 1⁄8 s; 1⁄4 s; 1⁄2 s; and 1 s. [3]
With this scale, each increment roughly doubles the amount of light (longer time) or halves it (shorter time).
Camera shutters often include one or two other settings for making very long exposures:
The ability of the photographer to take images without noticeable blurring by camera movement is an important parameter in the choice of the slowest possible shutter speed for a handheld camera. The rough guide used by most 35 mm photographers is that the slowest shutter speed that can be used easily without much blur due to camera shake is the shutter speed numerically closest to the lens focal length. For example, for handheld use of a 35 mm camera with a 50 mm normal lens, the closest shutter speed is 1⁄60 s (closest to "50"), while for a 200 mm lens it is recommended not to choose shutter speeds below 1⁄200 s. This rule can be augmented with knowledge of the intended application for the photograph, an image intended for significant enlargement and closeup viewing would require faster shutter speeds to avoid obvious blur. Through practice and special techniques such as bracing the camera, arms, or body to minimize camera movement, using a monopod or a tripod, slower shutter speeds can be used without blur. If a shutter speed is too slow for hand holding, a camera support, usually a tripod, must be used. Image stabilization on digital cameras or lenses can often permit the use of shutter speeds 3–4 stops slower (exposures 8–16 times longer).[ citation needed ]
Shutter priority refers to a shooting mode used in cameras. It allows the photographer to choose a shutter speed setting and allow the camera to decide the correct aperture. This is sometimes referred to as Shutter Speed Priority Auto Exposure, or TV (time value on Canon cameras) mode, S mode on Nikons and most other brands.[ citation needed ]
Shutter speed is one of several methods used to control the amount of light recorded by the camera's digital sensor or film. It is also used to manipulate the visual effects of the final image.
Slower shutter speeds are often selected to suggest the movement of an object in a still photograph.
Excessively fast shutter speeds can cause a moving subject to appear unnaturally frozen. For instance, a running person may be caught with both feet in the air with all indication of movement lost in the frozen moment.
When a slower shutter speed is selected, a longer time passes from the moment the shutter opens till the moment it closes. More time is available for movement in the subject to be recorded by the camera as a blur.
A slightly slower shutter speed will allow the photographer to introduce an element of blur, either in the subject, where, in our example, the feet, which are the fastest moving element in the frame, might be blurred while the rest remains sharp; or if the camera is panned to follow a moving subject, the background is blurred while the subject remains relatively sharp.
The exact point at which the background or subject will start to blur depends on the speed at which the object is moving, the angle that the object is moving in relation to the camera, the distance it is from the camera and the focal length of the lens in relation to the size of the digital sensor or film.
When slower shutter-speeds, in excess of about half a second, are used on running water, the water in the photo will have a ghostly white appearance reminiscent of fog. This effect can be used in landscape photography.
Zoom burst is a technique which entails the variation of the focal length of a zoom lens during a longer exposure. In the moment that the shutter is opened, the lens is zoomed in, changing the focal length during the exposure. The center of the image remains sharp, while the details away from the center form a radial blur, which causes a strong visual effect, forcing the eye into the center of the image. [4]
The following list provides an overview of common photographic uses for standard shutter speeds.
Motion picture cameras used in traditional film cinematography employ a mechanical rotating shutter. The shutter rotation is synchronized with film being pulled through the gate, hence shutter speed is a function of the frame rate and shutter angle.
Where E = shutter speed (reciprocal of exposure time in seconds), F = frames per second, and S = shutter angle: [15]
With a traditional shutter angle of 180°, film is exposed for 1⁄48 second at 24 frame/s. [15] To avoid effect of light interference when shooting under artificial lights or when shooting television screens and computer monitors, 1⁄50 s (172.8°) or 1⁄60 s (144°) shutter is often used. [16]
Electronic video cameras do not have mechanical shutters and allow setting shutter speed directly in time units. Professional video cameras often allow selecting shutter speed in terms of shutter angle instead of time units, especially those that are capable of overcranking or undercranking.
The depth of field (DOF) is the distance between the nearest and the farthest objects that are in acceptably sharp focus in an image captured with a camera. See also the closely related depth of focus.
A single-lens reflex camera (SLR) is a camera that typically uses a mirror and prism system that permits the photographer to view through the lens and see exactly what will be captured. With twin lens reflex and rangefinder cameras, the viewed image could be significantly different from the final image. When the shutter button is pressed on most SLRs, the mirror flips out of the light path, allowing light to pass through to the light receptor and the image to be captured.
In optics, the aperture of an optical system is a hole or an opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image of the aperture and focal length of an optical system determine the cone angle of a bundle of rays that comes to a focus in the image plane.
A camera is an instrument used to capture and store images and videos, either digitally via an electronic image sensor, or chemically via a light-sensitive material such as photographic film. As a pivotal technology in the fields of photography and videography, cameras have played a significant role in the progression of visual arts, media, entertainment, surveillance, and scientific research. The invention of the camera dates back to the 19th century and has since evolved with advancements in technology, leading to a vast array of types and models in the 21st century.
In photography, exposure is the amount of light per unit area reaching a frame of photographic film or the surface of an electronic image sensor. It is determined by shutter speed, lens F-number, and scene luminance. Exposure is measured in units of lux-seconds, and can be computed from exposure value (EV) and scene luminance in a specified region.
An f-number is a measure of the light-gathering ability of an optical system such as a camera lens. It is calculated by dividing the system's focal length by the diameter of the entrance pupil. The f-number is also known as the focal ratio, f-ratio, or f-stop, and it is key in determining the depth of field, diffraction, and exposure of a photograph. The f-number is dimensionless and is usually expressed using a lower-case hooked f with the format f/N, where N is the f-number.
A camera lens is an optical lens or assembly of lenses used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically.
In photography, flash synchronization or flash sync is the synchronizing the firing of a photographic flash with the opening of the shutter admitting light to photographic film or electronic image sensor.
In camera design, a focal-plane shutter (FPS) is a type of photographic shutter that is positioned immediately in front of the focal plane of the camera, that is, right in front of the photographic film or image sensor.
In photography, bracketing is the general technique of taking several shots of the same subject using different camera settings, typically with the aim of combining the images in postprocessing. Bracketing is useful and often recommended in situations that make it difficult to obtain a satisfactory image with a single shot, especially when a small variation in exposure parameters has a comparatively large effect on the resulting image. Given the time it takes to accomplish multiple shots, it is typically, but not always, used for static subjects. Autobracketing is a feature of many modern cameras. When set, it will automatically take several bracketed shots, rather than the photographer altering the settings by hand between each shot.
The science of photography is the use of chemistry and physics in all aspects of photography. This applies to the camera, its lenses, physical operation of the camera, electronic camera internals, and the process of developing film in order to take and develop pictures properly.
Aperture priority, often abbreviated A or Av on a camera mode dial, is a mode on some cameras that allows the user to set a specific aperture value (f-number) while the camera selects a shutter speed to match it that will result in proper exposure based on the lighting conditions as measured by the camera's light meter. This is different from manual mode, where the user must decide both values, shutter priority where the user picks a shutter speed with the camera selecting an appropriate aperture, or program mode where the camera selects both.
In photography, a shutter is a device that allows light to pass for a determined period, exposing photographic film or a photosensitive digital sensor to light in order to capture a permanent image of a scene. A shutter can also be used to allow pulses of light to pass outwards, as seen in a movie projector or a signal lamp. A shutter of variable speed is used to control exposure time of the film. The shutter is constructed so that it automatically closes after a certain required time interval. The speed of the shutter is controlled either automatically by the camera based on the overall settings of the camera, manually through digital settings, or manually by a ring outside the camera on which various timings are marked.
In digital photography, the crop factor, format factor, or focal length multiplier of an image sensor format is the ratio of the dimensions of a camera's imaging area compared to a reference format; most often, this term is applied to digital cameras, relative to 35 mm film format as a reference. In the case of digital cameras, the imaging device would be a digital image sensor. The most commonly used definition of crop factor is the ratio of a 35 mm frame's diagonal (43.3 mm) to the diagonal of the image sensor in question; that is, . Given the same 3:2 aspect ratio as 35mm's 36 mm × 24 mm area, this is equivalent to the ratio of heights or ratio of widths; the ratio of sensor areas is the square of the crop factor.
In photography and optics, a neutral-density filter, or ND filter, is a filter that reduces or modifies the intensity of all wavelengths, or colors, of light equally, giving no changes in hue of color rendition. It can be a colorless (clear) or grey filter, and is denoted by Wratten number 96. The purpose of a standard photographic neutral-density filter is to reduce the amount of light entering the lens. Doing so allows the photographer to select combinations of aperture, exposure time and sensor sensitivity that would otherwise produce overexposed pictures. This is done to achieve effects such as a shallower depth of field or motion blur of a subject in a wider range of situations and atmospheric conditions.
Image stabilization (IS) is a family of techniques that reduce blurring associated with the motion of a camera or other imaging device during exposure.
In cinematography and photography, panning means swivelling a still or video camera horizontally from a fixed position. This motion is similar to the motion of a person when they turn their head on their neck from left to right. In the resulting image, the view seems to "pass by" the spectator as new material appears on one side of the screen and exits from the other, although perspective lines reveal that the entire image is seen from a fixed point of view.
Sports photography refers to the genre of photography that covers all types of sports.
The Micro Four Thirds system is a standard released by Olympus Imaging Corporation and Panasonic in 2008, for the design and development of mirrorless interchangeable lens digital cameras, camcorders and lenses. Camera bodies are available from Blackmagic, DJI, JVC, Kodak, Olympus, OM System, Panasonic, Sharp, and Xiaomi. MFT lenses are produced by Cosina Voigtländer, Kowa, Kodak, Mitakon, Olympus, Panasonic, Samyang, Sharp, Sigma, SLR Magic, Tamron, Tokina, TTArtisan, Veydra, Xiaomi, Laowa, Yongnuo, Zonlai, Lensbaby, Venus Optics and 7artisans amongst others.
Landscape photography shows the spaces within the world, sometimes vast and unending, but other times microscopic. Landscape photographs typically capture the presence of nature but can also focus on human-made features or disturbances of landscapes. Landscape photography is done for a variety of reasons. Perhaps the most common is to recall a personal observation or experience while in the outdoors, especially when traveling. Others pursue it particularly as an outdoor lifestyle, to be involved with nature and the elements, some as an escape from the artificial world.
cinematography 360 shutter-angle shutter speed.