Table of Contents

    Welcome to the Photography Terminology page. Our mission here at Ditch Auto is to help educate photographers — whether they’re aspiring beginners or already in the thick of it.

    In pursuit of this mission, we have created the Photography Terminology page that lists and describes some of the most common and most important terminology in photography, including both hardware terms and the more theoretical aspects of creating images using light and color. Regardless of how experienced you may be, familiarizing (or refreshing your memory) with these terms and the concepts behind them will help you gain a better understanding of both the technical and artistic sides of the craft.

     


    AE Lock, FE Lock, and AF Lock

    AE Lock

    Auto Exposure Lock is a mode on all Canon EOS cameras. AE Lock sets the camera to the current exposure setting, regardless of future shutter or aperture changes. Unlike setting exposure manually, AE Lock enables the use of the built-in metering capabilities of the camera to easily pick and set an exposure.

    AE Lock is especially useful in filming video, as automatic exposure might cause unseemly changes in exposure while shooting, whereas AE Lock maintains a consistent exposure.

    FE Lock

    Flash Exposure Lock. Locks exposure to flash settings, often tied to AE Lock. Useful when using flash in hard to expose scenes.

    AF Lock

    Auto Focus Lock. AF Lock happens automatically when pressing the shutter button halfway. Locks focus to current Auto Focus target. This mode is especially useful when wanting the in-focus subject to the side of the frame.

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    Aperture

    Aperture is the adjustable size hole that light travels through. The term is also synonymous with the size at which the aperture is set to.

    The physical aperture of a camera is the mechanical system of blades in the lens that adjusts to various sizes. Lenses often have an aperture (or f-stop) specification, this indicates the maximum aperture the lens is capable of opening to.

    Adjusting the aperture of your camera specifies the size to which the aperture will open to when taking a photo. This is generally referred to as the f-stop. The f-stop is the aperture relative to the focal length of the lens, and is usually written as a power of the square root of 2: f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, etc, where f/1 is a larger (or wider) aperture than f/8.

    Aperture affects the focus of an image. A wide open aperture will have a shorter depth of field, whereas a more closed aperture image will have a much longer distance of the scene in focus. Photographers use this to their advantage to selectively focus or blur subjects at different distances.

    Low apertures (higher f-stop numbers) will require more time and sensitivity to achieve the same exposure as higher apertures (low f-stop numbers).

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    Aperture Priority Mode

    Often abbreviated to Av, AP, or A.

    Aperture priority mode is a semi-automatic mode on DSLR cameras that automatically adjusts both ISO and shutter speed settings to compensate for the manually set aperture. Aperture Priority mode is most useful when the photographer wants specifically to control depth of field.

     

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    Aspect Ratio

    Aspect ratio is the ratio between the height and width of the image. A landscape photo is an image that is wider than it is tall, and a portrait photo is taller than it is wide.

     

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    Autofocus

    Autofocus systems are built into cameras and used to focus on a selected point or area of the frame. Autofocus systems consist of optical sensor(s), control system or software, and motor to adjust the lens’ focus. Autofocus systems have evolved over the years to become significantly faster than adjusting manually, and some systems can automatically track and maintain focus on moving subjects.

    Autofocus systems come in two varieties: active, and passive. The former independently measures distance to the subject and adjusts the lens accordingly, while the later finds focus by analyzing the image passing through the optics. Many cameras use hybrid autofocus systems that combine two or more autofocus methods to achieve faster focus and/or to find focus in a greater range of scenarios.

     

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    Bokeh

    Bokeh is the aesthetic quality of blur produced in unfocused areas of a photograph, and is most visible in the most unfocused areas of highlight. The shape of bokeh is caused by the shape of the aperture in the lens. Through most lenses, bokeh appears as hazy circles. Bokeh can be intentionally used for composition purposes, often to create highlights or to make backgrounds or foregrounds intentionally hazy in order to draw focus to the subject. Some lenses are built specifically to alter the shape and quality of bokeh produced.

     

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    Bracketing

    Bracketing in photography is the technique of taking multiple photographs of the same subject at different exposures to either obtain a properly exposed photo, or to combine later for high dynamic range photography. Bracketing can also be used for multiple captures at different aperture or shutter speed settings.

    Automatic Bracketing is a feature in DSLR cameras that automatically captures multiple photos of the same subject at different exposure settings. Automatic bracketing can often be adjusted for number of captures and exposure values between each frame.

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    Buffer

    When taking a photo on a DSLR, the image sensor sends the image data to the camera’s buffer. The buffer is an area of memory built into the camera where image data is processed (and compressed) before being sent to the memory card. The size of the camera buffer affects how many photos can be taken in a given amount of time. High end DSLR cameras have continuous or burst shot modes, taking photos in quick succession. The speed and number of photos is dependent on the speed and size of the buffer.

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    Bulb Mode

    Abbreviated to B.

    In lieu of shutter speed being adjusted through the camera before the photo, bulb mode will keep the shutter open for as long as the shutter button is pressed. The term comes from the days when cameras were controlled with a pneumatic “bulb” the photographer squeezed to open and shut the shutter.

    Bulb mode is used when the photographer wants shutter speeds that are slower than the camera can be set to, and is often used for long exposure photographs such as for capturing fireworks, light paintings, and night sky photography.

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    Cable Release

    A cable release is a remote shutter button for cameras that support it. Cable releases can now be either wired or wireless, and are often used in combination with a tripod to further reduce camera movement, or to just operate the camera from a distance.

    Modern DLSRs can often use both wired cable releases, or remote shutters that use infrared, wifi, or bluetooth. Some camera manufacturers have enabled cameras to connect to other devices, such as a smartphone, that can act as a remote shutter.

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    Camera Flash

    A camera flash is either and internal or external light that illuminates the scene for better exposure. Flashes come in a myriad of styles, configurations, and capabilities.

    External Flash

    Many digital cameras come with a built-in flash, and most cameras come with the capability of working with external flash units. Cameras with the ability to fire external flash units are the standard in studio photography, and in situations where there needs to be either off-camera lighting, or lighting from multiple sources.

    Flash Sync

    Flash sync is the synchronization between the shutter exposing the sensor of the camera, and the flash being fired. Most flashes operate at 1/60th of a second, which means that if the shutter is open for less than that time, the sensor will not fully expose, resulting in black bars at the top and/or bottom of your photo.

    Flash Sync Speed

    Modern DSLR cameras offer “flash sync” shutter speeds that enable faster shutter speeds than would otherwise be possible to use with a flash. Flash Sync controls your camera operate differently than usual: while in normal operation, the sensor curtains (two frames inside the camera body that cover the sensor) open to expose the sensor fully to the image. With flash sync, the sensor curtains closely follow each other so that only part of the sensor is exposed. This operation happens faster than a flash. This enables using a much faster shutter speed while still being able to use a flash.

    Wireless Sync

    Cameras that offer flash sync have traditionally synchronized via a wire running from the camera to the flash unit. Modern technologies have enabled external flash units to be synced wirelessly. Wireless flash devices use various methods of syncing: radio transmission (either proprietary or a widespread technology like bluetooth), sensing other flashes fired, or infrared.

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    Camera/Lens System

    A camera or lens “system” usually refers to a set of camera bodies and lenses that share a common lens mount (the attachment mechanism between lens and camera body). There are several main camera systems that each have a variety of compatible lenses, camera bodies, and other accessories.

    Popular Systems

    Though a wide variety of systems have been used over the history of interchangeable lens cameras, a handful of systems account for the majority of systems in use today. Camera systems often vary by manufacturer, camera format, purpose, and price point.

    The most popular systems for modern digital cameras are Canon’s EF, EF-S and EF-M; Nikon F; Olympus’ Four Thirds and Micro Four Thirds; Pentax K; and Sony’s Alpha and E mounts.

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    Canon Focus Modes

    One Shot

    The default mode on Canon DSLRs. Locks focus when half pressing the shutter button. Useful for most situations (still life, portraits, landscapes, etc.)

    AI Servo

    AI Servo mode will keep continuous focus on a moving subject. Useful for any shots where the subject is moving, such as pets or for sports. Using continuous focus will drain the battery faster than One Shot mode, as the camera is working harder in both hardware and software.

    AI Focus

    AI Focus is a hybrid between the two previous autofocus modes, and is the default on cameras that have this capability. AI Focus will default to One Shot-style focus, but will auto focus if the subject moves.

    Manual Focus

    Focus is adjusted manually via the lens. Camera will not assist in focusing, and relies entirely on the eye of the photographer. Very useful when autofocus does not behave as desired.

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    Color Balance

    Color balance refers to the intensity and accuracy of color in a photograph. An image that is considered to be “balanced” is one where colors and brightness accurately match those found in the scene.

    White balance is considered the most important aspect of color balance, and specifies the intensity and accuracy of neutral colors (white to black, and shades in between).

    Auto White Balance

    Automatic white balance is a function of digital cameras. When set to auto white balance (often abbreviated to AWB), the camera assumes the given scene contains neutral colors, and adjusts the color balance to match that assumption. Often images taken using auto white balance will have inaccurate color temperature when the scene contains no (or very little) elements that are neutral.

    Color temperature

    In photography, color temperature usually refers to photos being either “warm” or “cold”. Cold photos have more blueish neutrals, warm photos will have more yellow or orangish neutrals.

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    Composition

    Composition refers to how a photograph is composed: the subject of the photo, its environment, how it is framed and angled, and how other objects in frame are utilized. The composition of photography is affected by a myriad of factors, and a photographer can focus on any number of these factors (or none at all) when composing a photograph.

    Rule of Thirds

    The rule of thirds is a guideline for photographic composition. The premise of the “rule” is that photos should be composed as if split into thirds both horizontally and vertically. When lines are overlaid onto a photo splitting it in thirds, a rectangle is formed in the middle. It is often suggested that a photo should be laid out to have the focal point be near one of the corners of this rectangle. Such a layout tends to create more tension and energy in a scene than when the focal point is near the center.

    Leading Lines

    Leading lines is a technique used to draw the focus of the viewer using lines or directionality found in the scene. For example, a photo taken when pointing down a straight road will often draw the eye towards the horizon, where the road and road markings point.

    Movement and Motion

    Photos can be taken with the intent of portraying motion (or lack thereof) in the scene. Many techniques can be used to emphasize the motion of all or part of the photo. Shutter speed can be used to create a “freezing of time” effect with a very fast shutter speed, or a slow shutter speed used to introduce motion blur. A photo composed of multiple exposures can show the movement of an object as it travels through the scene.

    Color

    Color composition can be used to create vibrance in a scene, evoke a specific emotion, or draw attention to a specific point or points. The eye of the viewer will be drawn to a colorful object in a neutral colored environment. Photos can often be made to evoke feelings of warmth and joy when the overall color balance of the photo is on the warm side. Conversely, a photo might feel sombre when the colors are cooler.

    Balance and Symmetry

    The “visual weight” of a photo is affected by the composition’s balance and symmetry. A photo that has most or all of its detail to one side or corner can often appear lopsided, and can create tension. Similarly, a photo that is extremely symmetrical might have a sterile or unnatural feeling to it. Photographs can be composed to intentionally evoke such feelings.

    Angle and Viewpoint

    The viewpoint from which photos are taken have an effect on the composition. Changing the angle of the photo can be used to change the background of the scene. Using an extreme angle can make the subject appear larger or smaller in the scene. Extreme angles can also create depth in a photo.

    Crop and Framing

    Perhaps one of the most important aspect of composition is what is in the frame. Specifically, how much space the subject takes within the frame. The crop and framing of a photo can emphasize or deemphasize the subject. The aspect ratio of a photo also has an effect. Aspect ratio is the ratio between the height and width of the image. A landscape photo is an image that is wider than it is tall, and a portrait photo is taller than it is wide.

    “Framing” is a technique where the subject of the photo is encompassed by other objects in the scene, creating a frame of the subject within the photo.

    Space and Complexity

    The number of objects and amount of space surrounding the subject of a photo can be used to alter the composition. Showing more or less space around the subject can show more or less context. Fewer objects in the frame create heightened visual impact for the objects that remain. Although creating a “busy” photo can also be intentional, and might suite the purpose of photographer.

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    Depth of Field

    The depth of field of an image is the distance between the nearest and farthest objects that appear in focus. A large depth of field with have more distance in focus, and a smaller depth of field with shorten the distance that is in focus.

    Depth of field is affected by lens aperture, the distance between camera and subject, and focal length of the lens.

    Images taken with larger apertures will have shorter depths of field, and less distance in focus. Appropriately, smaller apertures will have more of the scene appear in focus.

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    Dynamic Range

    Dynamic range is the ratio between the maximum and minimum luminance of a photo. A photograph that is said to have a high dynamic range will preserve more detail in highlight and lowlight areas.

    HDR

    While digital photo sensors have a significantly lower dynamic range than the human eye, there are techniques to overcome this limitation. High dynamic range (or HDR) photography achieve photos with a higher dynamic range by combining multiple exposures to retain detail in lighter and darker areas.

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    Exposure

    Exposure is the amount of light reaching the camera sensor. The term “exposure” can also refer to a single image capture. The exposure of a photo is determined by the amount of light from the scene, as well as aperture, shutter speed, and ISO settings.

    EV

    Exposure value (often abbreviated to EV) is a measurement of exposure that is relative to the aperture and shutter speed settings. For example, a photo with a long shutter speed and low aperture can have a similar EV as a photo with a shorter shutter speed and higher aperture.

    When using a camera that shows an EV measurement, one can adjust shutter speed and aperture to obtain a desired effect while maintaining exposure.

    Photos that are overexposed will have areas that appear white and have reduced detail. Conversely, an underexposed photo will have areas that appear black and lacking detail. A photograph that is “properly” exposed with have a minimum of overexposed and underexposed areas.

    Photos can be intentionally overexposed or under exposed purposely to achieve a specific effect. For example, overexposing a photo to wash out whites, or underexposing to reduce shadow detail. See Composition.

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    Flash Memory

    Flash memory is the storage medium for DSLR cameras. Most digital cameras today use either SecureDigital (SD) or CompactFlash (CF) removable flash memory cards. Memory cards are rated by their size (the amount of storage), and speed (the rate at which data can be written to the memory). Larger size cards will hold more photos, and faster cards will be able to store photos quicker.

    When purchasing memory for your camera, consider the size and speed of the card, as well as the resolution of your camera, and the environment you will be shooting in. How high is your camera’s resolution? The higher the resolution, the faster and bigger your flash card needs to be in order to maximize the number and speed of photos you can take. How many photos will you be taking? Will you be in an place where you can transfer the photos from the card to a computer? Larger cards enable taking more photos before swapping cards or transferring and wiping the current card.

    Memory Speed

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    Focal Length

    Focal length, almost always measured in millimeters, is the distance between the sensor and the focus point, where the image appears sharpest through the lens, and determines the magnification of the lens.

    Focal length directly affects the field of view, or crop, of a photo. Smaller focal lengths have a wider field of view, and larger focal lengths have a smaller field of view. For example, a “wide angle lens” (a lens with a low focal length) will show more of the scene, and a telephoto (higher focal length) lens will show less.

    Every lens has either a fixed or variable focal length. A fixed length (or prime) lens has a fixed “field of view” or zoom level, whereas a lens with a focal length range (for example, 24-70mm) is what’s known as a zoom lens, with an adjustable field of view.

    Generally, lenses of lower, fixed focal lengths (like a 20mm lens, often referred to as a pancake lens) will contain fewer lens elements. As the focal length grows, more lens elements are introduced, and the image must pass through more pieces of glass to the image sensor in the camera.

    Lenses with fewer lens elements are usually capable of producing sharper images with less distortion than lenses with more elements. More elements also reduces the amount of light reaching the sensor.

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    Focus

    Focus is the area (more specifically, the exact distance) in a photo that appears sharpest. The focus of a photograph is affected (and determined) by the camera’s lens element geometry.

    Focus is also used interchangeably with the term “focal point”, and refers to the point or area of a photograph that most draws the eye. The focal point of an image can be either intentional or accidental, is affected my many aspects of the image such as color or focus, and can vary between viewers.

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    Image Sensor

    Image sensors are the device in digital cameras that convert the optical image into digital information. The two main specifications of image sensors are resolution (The vertical and horizontal pixel count, most often cited in megapixels) and crop factor.

    CCD and CMOS

    The vast majority of image sensors use either charge-coupled device (CCD) or active pixel sensor (CMOS) technology. Though both technologies have advantages and disadvantages, most image sensors are CMOS sensors.

    Since each pixel in a CCD sensor is analog, pixel data must be converted to a voltage and processed into digital data separately. This process requires more power and time to capture an image. CCD sensors also use a full-frame electronic shutter method, which exposes the entire sensor at once, and is a slower method than a rolling shutter (and thus recording HD video is more difficult). CCD sensors generally perform better in low light shooting than CMOS (though the latest technologies make this difference negligible), and the full-frame shutter prevents image distortions caused by rolling shutter.

    Active pixel sensors, alternatively, can capture and immediately convert light information into voltage and then digital data, forgoing the need to be processed, and eliminating the additional conversion circuitry needed in CCD sensors. Fewer steps between converting light into data enables capturing images faster and lower power consumption. Active pixel sensors are commonly called CMOS sensors as they are built using the ‘Complementary Metal–Oxide–Semiconductor’ technology.

    Crop Factor

    Crop factor is the size of the sensor relative to the size of the 35mm reference frame. This measurement is used to determine (roughly) the performance of the sensor, as well as the amount of image that is cropped when using SLR lenses on film cameras. On most DSLR cameras, this factor is usually between 1.3x and 2x. The amount refers to the magnification of the image compared to a 35mm-sized sensor, where 1x would be equal to 35mm, and 2x would be half the size.

    In general, sensors that are larger (crop factors closer to 1 or lower) perform better, as each pixel is accordingly larger, and therefore better capable of capturing light.

    Sensor Format

    Most digital cameras have sensors of uniform sizes, known as formats. The most common format is APS-C (Advanced Photo System type-C), which is a specification for sensors that have a dimension of approximately 24 x 16 mm, and a crop factor of 1.5.

    Canon has a unique size of APS-C with a crop factor of 1.6x, as well as a larger APS-H sensor with a crop factor of 1.3x.

    Some high end DSLR cameras have “full frame” sensors, which bear the same dimensions as a frame of 35mm film (36mm x 24mm).

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    ISO

    ISO generally refers to a measurement of light sensitivity. ISO is the most widely used measurement of light sensitivity, though there are other systems such as ASA.

    The term “ISO” actually refers to the organization that developed the rating, the International Organization for Standardization (the french name being shortened to ISO). In English, the term ISO has been coopted to refer to the organization’s light sensitivity rating.

    In photography, ISO is the speed at which an image becomes exposed. Lower ISO numbers indicate longer, and higher numbers indicate shorter time to reach full exposure.

    In digital photography, camera sensors can be adjusted to different ISO speeds, and is used in conjunction with aperture and shutter speed to adjust exposure.

    Faster ISO speeds, while taking less time to expose, adds noise to your image. A photo taken at a higher ISO will have more color aberrations between pixels.

    When shooting in manual mode, a low ISO setting will produce a sharper image, but will require more light to hit the sensor. This requires setting the lens to a higher aperture, a faster shutter speed, or both. Shooting in higher ISO settings will require less light, but will lose detail and sharpness.

    Digital cameras often advertise extremely high ISO ratings, but often produce images that are extremely noisy.

    In the days of film, ISO was usually called “Film Speed”, or the speed at which a frame of film could become fully exposed. In film photography, the ISO is determined by the film itself, and one could buy different speed films for varying needs. The most common films were of ISOs between 100 and 400.

    Auto ISO

    Digital cameras usually come with an Auto ISO setting that will approximate the necessary ISO setting based on scene light and camera settings. This setting can often be set to have a minimum and maximum ISO that can be used.

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    Lens

    The lens is one or more transparent materials that are used to focus light. In the context of digital photography, lenses are most often made of glass and are used to focus light onto the image sensor to create a sharp image. Without a lens, a digital image sensor will capture light beams from any angle that it is exposed to and creating a blurry, unfocused image.

    Camera lenses consist of a series of transparent glass ‘elements’ (each of which is, in itself, a lens). Each element uses convex, concave, or flat sides to focus and/or magnify light beams. Lenses can be configured for various and specific purposes using groups of elements varying in size, configuration, order, spacing, lens surfaces, and more.

    Lenses are usually built with an iris diaphragm consisting of a series of blades that create an adjustable hole to control the amount of light passing through the lens.

    Lens Types

    Lenses come in various types to provide functions like zoom and stabilization or to achieve a certain effect, but lenses can be split between to categories: fixed focal length, and adjustable focal length. Fixed focal length lenses are most often referred to as simply ‘fixed’ or ‘prime’ lenses, and have a set focal length that captures one field of view size. Adjustable focal length lenses are usually called ‘zoom’ lenses, and have an adjustable focal length that allows changing the size of the field of view captured. See Focal Length above for more information.

    Within the two main categories are various specialized lenses for various applications. Some examples include ‘macro’ lenses for close-up photography, fisheye lenses for extremely wide fields of view, and perspective control or ’tilt/shift’ lenses.

    Lens Mount

    Lens Mount refers to the mechanism for attaching the lens to the camera body. Modern lenses are created for a specific lens mount or ‘camera system’ to be compatible with a camera or series of cameras. See Camera System above for more information.

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    Metadata

    Images taken by digital cameras contain both the optical information captured from the image sensor, as well as information about the image. This additional information is called metadata. This metadata often includes datum such as filename, capture date and time, the camera model and settings used, and geographic information if the camera supports it.

    EXIF data

    EXIF is short for Exchangeable image file format, and is a metadata specification for image and audio files, and is an area of the file that contains metadata information.

    Geotagging

    Photos taken with a device that has access to geolocation data can tag that information in the metadata of an image. Images that have this location data are referred to as “geotagged”.

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    Metering

    Digital cameras come equipped with built in light metering. A light meter adjusts the camera for proper exposure, and usually has options for different methods and locations. The most common metering method is “spot metering”, which adjusts the exposure based on a single spot in the frame, though most cameras include multiple options for metering.

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    Noise

    Noise refers to the variations in color and brightness between pixels in an image where one would otherwise expect uniformity. This effect is most prevalent when shooting with a very high ISO setting and in very low light scenes.

    In layman’s terms, noise is caused by the image sensor not receiving enough data to accurately determine the exposure of each pixel, and thus having to “guess” its color and brightness.

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    Program Mode

    Often abbreviated to P.

    Program mode is a semi-automatic camera shooting mode that automatically sets shutter speed and aperture.

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    Shutter

    The shutter is used to control the amount of time a camera’s sensor is exposed to light. Mechanical shutters work by using a physical element to block light from hitting the sensor and moving out of the way for a set amount of time (see shutter speed) during exposure.

    Shutter mechanisms are usually built into the camera body and use various methods to block and expose the sensor. Most DSLR cameras use a ‘focal-plane’ type of shutter mechanism that usually consist of two ‘curtains’ to control the exposure of the sensor. Depending on shutter speed or flash sync settings, the curtains can move simultaneously or individually, and can expose the entire sensor or a part of it at once.

    Electronic Shutter

    An electronic shutter is method for image sensors to replicate the functionality of a mechanical shutter. Electronic shutters operate by charging (enabling for exposure) the sensor for a set amount of time. Eliminating the need for a mechanical shutter enables image sensors to be used in smaller spaces, such as in smartphones. Electronic shutters also allow for extremely fast shutter speeds, but come at the cost of additional noise image noise (although the latest sensor technologies greatly reduce this effect).

    Rolling Shutter

    Rolling shutter refers to a method of shutter operation for both mechanical and electronic shutters, and is the most common shutter method in capturing digital video. A rolling shutter works by moving either horizontally or vertically across the image sensor to expose a small cross section using a physical shutter, or with an electronic shutter by charging a section of pixels.

    Rolling shutter, while very efficient, can cause effects like skewed images when shooting fast-moving objects (such as helicopter blades), wobbly or smeared images and video when the camera is moving rapidly while recording, or partially exposed images when the flash or other sources of light fire faster than it takes for a whole frame to be exposed.

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    Shutter Priority Mode

    Often abbreviated to S or Tv.

    Shutter priority mode is a semi-auto mode on DSLR cameras that automatically adjusts both ISO and aperture settings to compensate exposure for the manually set shutter speed. Shutter Priority is most useful for capturing movement with the desired effect, such as capturing motion blur, or “freezing” the subject in frame.

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    Shutter Speed

    Shutter speed refers to the time the camera’s shutter is open. Usually denoted in seconds or fractions of a second, such as 1s, 0.5s, or 1/320.

    When the shutter is open, the sensor (or frame in film photography) is exposing. For example, a photo shot at 1/1000 means that light is hitting the sensor for one thousandth of a second.

    Shutter speed affects the sharpness of an image. The longer the shutter is open, there is more time and opportunity for the camera to move, making the image blurry. This is caused by photons from the same origin moving across the sensor and exposing different pixels. The same is also true for a moving subject, even if the camera is not moving.

    Shorter shutter speeds (larger fractions of a second) makes capturing moving subjects (or using a moving camera) easier, but also requires a larger aperture, higher ISO, or both in order to capture a photo with the same level of exposure.

    Short shutter speeds can produce images that have the effect of freezing a fast moving subject, or keeping the subject in focus while the environment becomes blurred with motion. Alternatively, “long exposure” photos (photos with longer shutter speeds) can be used to create images with intentional blur, or light painting photos.

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    Video

    Most of today’s digital cameras include functionality for recording digital video. Today’s high-end DSLR cameras, with their relatively small size, high quality interchangeable lenses, and highly adjustable shooting modes, have become the de-facto entry point for high quality videography. DSLR video is even being used for television and movie production.

    HD Video

    Digital video currently comes in two main resolutions (with a third, higher resolution, becoming more mainstream): standard definition, and high definition (HD). Standard definition is usually considered to be any resolution with a vertical height of less than 720 pixels (abbreviated to 720p), and high definition is 720p and above. 1080p is considered “Full HD”, and is the most prevalent resolution for today’s flat panel televisions, and most television broadcasts are now in the same resolution.

    Higher resolutions are becoming more prevalent in both monitors and television sets, as well as recording equipment. Ultra High Definition (UHD) resolutions typically start at 2160 vertical pixels and above, which, when combined with width, has four times as many pixels as Full HD.

    Frame Rate

    The frame rate of digital video is the number of frames in one second of footage. The frame rate of video plays an important part of how video looks. Whereas many digital video recording devices record at 30fps or higher, movies are almost always filmed at 24 frames, which gives it a “cinematic” appearance. Very high frame rates usually creates video that appears artificial, sometimes called the “soap opera effect”.

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