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Glossary of Photographic Terms

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Contents

1. Introduction 1. Glossary

Terms in Alphabetical Order: 1. A 2. B and C 3. D 4. E and F 5. G 6. H and I 7. J, L and M 8. N and O 9. P and R 10. S 11. T, U, V, W, X and Z 11. Further Information

Glossary of Photographic Terms

Note: This publication has not been updated and are classified as D-type AF Nikkor since it was last published. Some of the . hyperlinks may have changed and may need updating. In addition, some of the information AF or Auto Focus in this publication may be out of date. Most modern SLR lenses have this function now. The automatically focuses on the subject as quick as the eye. With an SLR you Introduction can normally select manual focus if The following glossary contains terms necessary. What is a ? relating to digital including SLR and AI (Nikon) DSLR cameras as well as photographic The term camera Automatic index; Nikon's system for telling comes from the the camera's meter what the lens' effects. The list may not be complete as new maximum is. terms and acronyms are arising all the time. (Latin for "dark

AI/S (Nikon) chamber"), an early Automatic index/; Nikon's lens mount mechanism for permitting automatic operation in shutter- projecting images. Glossary priority and program auto-exposure The modern camera systems. evolved from the camera obscura. A Aliasing This is an effect caused by sampling an AA Filter image at too low a rate. It causes rapid Most Digital SLR's have a "Low Pass Filter" change (high texture) areas of an image to (LPF) or AA (Anti-Aliasing) Filter in front of appear as a slow change in the sample the CCD or CMOS sensor. This helps to image. Once this has happened, it is eliminate colour aliasing problems, or the extremely difficult to reproduce the original "moire" effect. image from the sample.

ACR (Adobe Camera Raw) This is the program that comes up by default This is calculated by the of the in CS3 when you open a RAW file. It is the lens and the size of the . The program used to make the initial 35mm equivalents differ according to the adjustments before transferring the RAW file sensor size. to CS3, making further adjustments and then saving as .tiff, .jpg etc. Aperture The lens opening that allows more, or less Adjustable Camera light onto the sensor formed by a diaphragm A camera with manually adjustable settings inside the actual lens. It is measured in for distance, lens openings, and shutter f/stops. speeds. Aperture Priority Adjustable-Focus Lens Often abbreviated as A or Av (for Aperture A lens that has adjustable distance settings. value) on a camera mode dial. It is a setting on some cameras that allows the user to Adjustment Brush choose a specific aperture value while the There are many new features in the camera selects a to match. Lightroom 2 photo software but the main The camera will ensure proper exposure. one is the adjustment brush. This powerful This is different from manual mode, where tool enables you to make local adjustments the user must decide both values, shutter to your photos with any combination priority where the user picks a shutter speed exposure, brightness, contrast, saturation, with the camera selecting the aperture to clarity, sharpness, and colour settings. match, or program mode where the camera selects both. AE Automatic Exposure: Three kinds are Aperture Priority AE available - programmed auto exposure, When using this mode, the user selects the aperture-priority auto exposure and shutter- aperture giving control over the Depth of priority auto exposure. Field. A large aperture letting more light in gives a small , meaning not AE Lock much will be in focus. Whereas a small Used to hold an automatically controlled aperture, not letting much light in, will give a shutter speed and/or lens aperture, in case greater depth of field or more will be in focus you need to recompose your picture but from the front to back of the image. want to retain an previous exposure reading. APO AF-I (Nikon) Apochromatic; a type of lens which focuses Lens with built-in autofocus drive motor. CPU different wavelengths of light on the is also built in. AF-I Nikkor lenses send plane for improved image sharpness. information on distance to the camera body Especially useful in telephoto lenses. ( is corrected).

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Glossary of Photographic Terms

AS cloud. Where two shadows overlap, the Antishake - often understood to be the same shadow is called umbral (see also Fog Bow). as Image Stabilization, but may only refer to a camera automatically increasing ISO. Buffer Temporary storage areas held in your ASA camera or computer’s RAM. Its acts as a

American Standards Association. (also see temporary holding area for data that will be ISO). manipulated by the processor before saving What is it to another device. For example if you are ASL shooting in continuous mode, when the RAM Photography? Aspherical Lens: allows for high quality, yet buffer on your is full it will “Photography is compact and lightweight lenses. slow to a much slower rate while the buffer the art, science empties to your compact card or other and practice of Aspect Ratio device. creating durable The ratio of horizontal to vertical dimensions images by of an image. For example, 35mm slide film = recording light or 3:2, TV = 4:3, HDTV = 16:9, 4x5 Film = other 5:4. C electromagnetic radiation, either Aspherical Lens CAF electronically by A lens with edges flattened so that it is not a CAF stands for Continuous Auto Focus. What means of an image perfect sphere. These produce a much continuous auto focus does is it takes the sensor or superior image. most prominent object in your shots’ chemically by composition and it uses this as its focal means of a light- Automatic Exposure point. However, the system is not always sensitive material The camera sets the shutter speed and perfect at guessing what you want that such as aperture for the correct exposure according object to be. You can compensate for this by to the light. . into the object you want to be in Typically, a lens is focus, hold that zoom until the object is used to focus the Average Metering sharp, and then slowly zoom out. light reflected or In this the camera will use the light information coming from the entire Card Reader emitted from scene and averages for the final exposure Used for transferring data from your flash objects into a real setting, giving no weighting to any particular memory card to your PC. A better way of image on the light- portion of the metered area. transferring your image files than connecting sensitive surface the camera to your PC. Sometimes the inside a camera AWB cameras circuitry can become corrupt. during a timed This stands for Automatic White Balance. exposure. The Most digital cameras have this feature where CCD (Charged Coupled Device) result in an the camera sets the white balance. Override This is a light sensitive chip used in your electronic image is available in most DSLRs. digital camera for image gathering. The CCD sensor is an

Pixels gather the colour from the light and electrical charge at B pass it to the shift register for storage. CCD's each , which is are analogue sensors, the digitising occurs electronically when the electrons are passed through the A processed and B & W to D converter. This "Analogue to Digital" stored in a digital Abbreviation for . converter converts the analogue signal to a image file for digital file or signal. Barrel Distortion subsequent display A common geometric lens distortion causing Centre-Weighted Average Metering or processing.” an acquired image to pucker towards the In this system, the meter concentrates Wikipedia centre and be rounded along the outer between 60 to 80 percent of the sensitivity edges. towards the central part of the viewfinder. The balance is then "feathered" out towards B (Bulb) the edges. Some cameras will allow the user At the B setting, the shutter remains open as to adjust the weight/balance of the central long as the shutter release button remains portion to the peripheral one. One advantage fully depressed. of this method is that it is less influenced by small areas that vary greatly in brightness at Bracketing the edges of the viewfinder: as many Take a series of pictures taken at different subjects are in the central part of the frame, exposures. consistent results can be obtained.

Brocken Spectre Channel The Brocken Spectre is basically a shadow One piece of information stored with an (the photographer's shadow) cast on and in image. For example, a true colour image has a cloud (fog). As the cloud is not an object 3 channels, red, green and . with a sharp boundary, but more or less transparent to some optical depth, the shadow figure is a three-dimensional image cast not only on the cloud but also in the

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Glossary of Photographic Terms

Chroma The colour of an image element or pixel. A D chroma is made up of saturation plus the hue values but is separate from the Dark Frame luminance value. A noise reduction process where a camera takes a second exposure of a black frame after CIFF the camera takes a long exposure image. The This stands for Camera Image File Format - image noise is easily identified in the black an agreed type of image storage used by frame and is then electronically removed many camera makers. from the actual image. This helps to reduce the amount of hot that normally show Close-Up up in long exposure shots from digital The general term for pictures taken at cameras. relatively close distances, from 1/10 life-size (1:10) to life-size (1:1). Dedicated Flash An Electronic Flash Unit that is made to be used directly with a specific make or model of A colour cast is a tint of a particular colour, a camera. Canon, Nikon Minolta and Olympus usually unwanted, which affects the whole of for example, all have electrical contacts in the a photographic image evenly. Certain types hotshoe which passes TTL (through the lens) of light can cause film and digital cameras to metering and AF range information to and have a colour cast. In general, the human from the flash unit or speedlight. eye does not notice the unnatural colour, because our eyes and brains adjust and Depth of Field (or DOF) compensate for different types of light in The range of acceptably sharp focus in front of ways that cameras cannot. and behind the distance the lens is focused on. This is controlled by the focal length and CMS aperture opening of a lens. A large or wide Colour management system. A software aperture gives a shallow depth of field (not program designed to ensure colour matching much range in focus) and a smaller or narrow and calibration between video and/or aperture give a large depth of field (more computer monitors and any form of hard range in focus). copy output. Diaphragm CMYK A series of metal "blades" that can be This stands for , Magenta, Yellow and manipulated to form a larger or smaller BlacK. Colours used by most printers to opening through which the light is admitted. produce your prints. Diffusion Filter Coating A diffusion filter is a translucent A layer or multiple layers of thin anti- photographic filter used for a . reflective materials applied to the surface of When used in front of the , a lens elements to reduce light reflection diffusion filter softens subjects and (flare) and increase the amount of generates a dreamy haze. This can also be transmitted light. improvised by smearing petroleum jelly on a UV filter or shooting through a nylon Codec stocking. Diffusion filters may be uniform or A Codec compresses information to enable it may have a clear central area to create a to be sent across a network much faster. It vignette of diffused area around the clear will also decompress information received via centre subject. the network. Digital Imaging Colour Balance The new evolution of the art of photography The accuracy with which the colours captured where images are scanned into an electronic in the image, match the original scene. format and then "processed" with software such as Adobe Photoshop: see Compression www.adobe.com/products/photoshop.html A digital creates an image file that is enormous. To enable image files to become Dioptre Adjustment smaller and more manageable cameras employ There should be a knob or dial near the some form of compression such as JPEG. RAW viewfinders but not all cameras have and TIFF files have no compression and take this feature. Dioptric adjustment allows for up more disk space. fine-tuning of the viewfinder focus to suit an individual’s eyes. The process is essential to CRW ensure that both the image on the focusing The RAW CCD file format used by Canon screen and the viewfinder display information Digital Cameras. The acronym is derived from are in perfect focus. Canon RAW.

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Glossary of Photographic Terms

Distance Scale Exposure Bracketing The main use of distance scale comes with This is where the camera will take 3 or 5 (that is, taking pictures images and varies the exposure up or down for at a very close distance). Auto-focus often each photograph ensuring at least one will be does not work well at close range. Setting well exposed. the distance scale at a low distance or in the macro range reduces the amount of focus fine-tuning. Modifying the shutter speed and/or lens aperture recommended by the camera's light DSLR meter in order to produce special creative Digital Single Lens Reflex (SLR) – a camera effects or to meet special requirements. You with interchangeable lens. can lighten or darken the image by under or over exposing the image. Factors considered DX-Coding may include unusual lighting distribution, Code printed on film cartridges providing most variations within a camera system, filters, non- new cameras with information. standard processing, or intended underexposure or overexposure. (or DR) This expresses the luminance range of a scene, a captured image or the maximum F range of luminance that a camera can capture at one setting. It describes the ratio F-Stop between the maximum and minimum This a number indicating the size of the measurable light intensities (white and aperture. It is an inversely proportionate black, respectively). number as in F2.8 is a large opening and F16 is a small opening.

E Fill-Flash Exposure consisting of a combination of flash Element and "available light" balanced to produce a One piece of comprising the internal pleasing mix of the two. of a lens. (See Group). Equivalent (or Equivalence) Exposure An ultra-wide angle lens which purposely An equivalent exposure is one that relies on introduces barrel distortion so straight lines the same amount of light for the proper near the edges of the frame appear to curve exposure but juggles the aperture and out. shutter speed settings to yield different image effects. Fixed Aperture The aperture remains constant regardless of EOS (Canon) the lens' focal length. For example, the Electronic Optical System; Canon's current line Canon "L" series have a constant fixed of autofocus cameras and accessories. aperture when zooming.

E-TTL (Canon) Fixed Focal Length Lens The acronym stands for Evaluative, through- Basically, this is a non . 100mm, the-lens flash metering. This system uses a 50mm, 200mm etc. brief pre-flash before the main flash in order to calculate the correct exposure. Flare Image degradation caused by stray light EV which passes through the lens but is not ; A number that represents focused to form the primary image. This is available combinations of shutter speed and often caused by light bouncing off internal aperture offering the same exposure effect air-to-glass surfaces. when scene brightness remains the same. Each EV number can be applied to various Flash (or Flash Gun/Flash Unit) shutter speed and aperture combinations. A flash is a device used in photography producing a flash of artificial light (typically EXIF 1/1000 to 1/200 of a second) at a colour This stands for Exchangeable Image File temperature of about 5500 K to help Format. It provides embedded information illuminate a scene. A major purpose of a about camera and exposure for each image. flash is to illuminate a dark scene. Other Most decent graphics programs can read this uses are capturing quickly moving objects or information. changing the quality of light. Flash units are commonly built directly into a camera. Some Exposure cameras allow separate flash units to be Light striking a sensitised material (film or mounted via a standardised "accessory paper emulsion). mount" bracket ().

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Glossary of Photographic Terms

Flash Gamut A flash diffuser spreads the light from the This is the range of colours that are available flash of a camera. In effect, the light will not in an image or output process. Gamut is come from one concentrated source (like a generally used in describing the capabilities spotlight), but rather will spread out, bounce of a printer to reproduce colours accurately from reflective ceilings and walls, thus and vibrantly. getting rid of harsh light, and hard shadows. This is particularly useful for portrait GIF photographers, since harsh light and hard Graphic Image File format mainly used for shadows are usually not considered flattering Web graphic or small animated (GIF) files. in a portrait. Not good for as it only contains a maximum of 256 colours. Focus Assist Cameras with this feature send out a light, GND either normal or infra-red to light up the Graduated Neutral Density. A type of neutral subject to assist with the autofocus in low density filter in which brightness is reduced light or darkness. more on one side of the filter than on the other, allowing the photographer to reduce Focal Length the contrast between, for example, bright A lens' angle of view, such as: Wide angle, sky and dark land. standard or telephoto. It is the distance from the optical centre of a lens to the image Golden Rectangle plane when the lens is focused to infinity. An image ratio (width vs height) that makes the most pleasing, balanced impression on Focus Lock the viewer. Panoramic images are long and Focus lock means pre-focussing the subject skinny; square negatives often make it hard and re- by moving the camera. This for the viewer to recognize the central focus is done by half pressing the shutter to focus of a composition. A 35mm format is pretty and fully pressing to expose. This is done, close to a golden rectangle. Also see for example, to ensure crisp, sharp eyes. .

Focal Plane (or FP) Gradation A shutter that opens and closes near to the A smooth transition between black and film or image sensor, usually as a fast- white, one colour and another or colour and moving slit, as contrasted with a bladed/leaf no colour. shutter located near a nodal point of a lens. Grey Level Fog Bow This is the brightness level of a pixel A fog bow is a similar phenomenon to a representing its lightness from black to rainbow, however, as its name suggests, it white. It is usually defined as a value from 0 appears as a bow in fog rather than rain. to 255, with 0 being black and 255 being Because of the very small size of water white. droplets that cause fog—smaller than 0.05 millimetres (0.0020 in)—the fog bow has Grey Scale only very weak colours, with a red outer A term used to describe an image containing edge and bluish inner (see also Brocken shades of grey rather than colour. Most Spectre). commonly referred to as a black and white photograph.

G Group Two or more elements cemented together within a lens. Lenses are described as having Measure of the amount of contrast in an a certain number of elements in a certain image according to the properties of a smaller number of groups. gradation curve. High contrast = High Gamma and Low = Low. The power of a flash in relation to ISO film Gamma Correction speed. Guide numbers are quoted in either With reference to displaying an image meters or feet. (To convert from meters to accurately on a computer screen, Gamma feet, multiply the metric number by 3.3). correction controls the overall brightness of Guide numbers are used to calculate the an image. Images which are not properly f/stop for correct exposure as follows: corrected can look either too dark or f/stop=guide number/distance. bleached out. Guide Number The power output rating of a speedlight flash unit.

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Glossary of Photographic Terms

Internal Focusing (and Internal Focus H Lens) An internal focus lens (sometimes known as Halftone Image IF) is a photographic lens design in which An image reproduced through a special focus is shifted by moving the inner lens screen made up of dots of various sizes, to group or groups only, without any rotation or simulate shades of grey in an image. shifting of the front lens element. This makes it easy to use, for example, a screwed-in polarizing filter or a petal shaped Hipstamatic is a . During macro photography, using application for the Apple iPhone. It uses the an internal focus lens reduces the risk of the iPhone's camera to allow the user to shoot front of the lens accidentally hitting the square photographs, to which it applies a subject during focusing as the front element number of software filters to make the does not move. The physical size of an images look as though they were taken with internal focusing lens does not change an antique film camera. The user can choose during focus, nor does the front of the lens among a number of effects which are rotate. This is particularly useful for large presented in the application as simulated lenses, keeping the size more compact, or lenses, and flashes. Several of these when using filters or accessories mounted on are included with the application, while the front of the lens that may require careful others may be acquired through an in-app alignment. One issue internal focusing lens purchase. can have is that the true focal length of the lens is reduced when not focused at infinity. Hot Shoe A mounting device, usually built onto the top IQ - Image Quality of a camera that enables a flash unit, or Image quality is a characteristic of an image speedlight, to be mounted on and triggered that measures the perceived image by the camera. degradation (typically, compared to an ideal or perfect image). Imaging systems may Hue introduce some amounts of distortion or A term used to describe the complete range artefacts in the signal, so the quality of colours of the spectrum. Hue is the assessment is an important problem. component that determines just what colour you are using. In gradients where you use a Image Resolution colour model in which hue is a component, This relates to the number of pixels per unit you can create some rainbow effects. length of image. E.g. pixels per inch, pixels per millimetre, or pixels wide etc. The hyperfocal distance is the point at which Image Sensor you should focus your lens to allow you to Digital cameras use an electronic image sensor get maximum depth of field (DOF). Once (CCD or CMOS), to gather the image data, focused on this point, everything from half whereas a traditional camera exposes light to the hyperfocal distance to infinity will be emulsion film, sharp. Image Stabilization (IS) An optical or digital system built in to a lens I for removing or reducing camera movement, most effective with telephoto or telephoto zoom lenses. Can be found on most of Canon's i-TTL "L" range of lenses as well as mid-range lenses Similar to Canon's "E-TTL", Nikon's new flash such as the EF 28-125 IS USM exposure system is used on the new D70 DSLR and SB-600 and SB-800 Speedlights. Interlaced This is the term used to describe an image ICC Profile sensor that gathers its data by first processing "The International Colour Consortium" is a the odd lines, and then processing the even group that sets the standard guidelines for lines. colour management in the imaging world. Colour profiles simply let one piece of Intervalometer (or Interval Recording) hardware or software know how another Another term for Time Lapse Photography. You device or image has created its colours and can capture an image or images at pre-set how they should be interpreted or reproduced. intervals automatically. Good quality remote releases have this function built in, meaning iESP you don't have to stand around pressing the Olympus' exposure metering system. shutter every 5 or 10 seconds. iLink Sony's term for the IEE-1394 FireWire data port found on Sony camcorders.

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Glossary of Photographic Terms

IR (Infra Red) Lightroom (also LR) This uses a beam of light that is invisible to us Lightroom, a popular software application humans to either control a device without from Adobe for processing images from wires or as a method of transferring data from digital cameras. camera to computer (or printer) without cables. Some cameras also employ infrared in Lossless the auto focusing system. This refers to storing an image in a non- compressed format, such as TIFF. ISO International Standards Organization; the Low Pass Filter number represents the film's sensitivity to Most DSLR's (Digital SLR's) employ a Low light. A higher ISO number indicates the film is Pass Filter (LPF) or Anti-Aliasing (AA) filter in more sensitive and requires less light for a front of the sensor to help eliminate proper exposure. problems with colour aliasing (moiré).

J M

JFIF (Also known as EXIF) Macro Focusing This is a specific type of the JPG file format. Macro focusing, applied to zoom lenses, moves the lens group(s), enabling the lens to focus JPEG (Joint Photographic Experts closer than the normal focusing distance from Group) close-up shooting. This is the name of the committee that designed the standard image compression Matrix algorithm. Auto-exposure metering where the camera sets both aperture and shutter speed JPG according to data stored in the camera's built- This is the most common type of compressed in memory, comparing the scene to be image file format used in modern cameras. photographed to reference scenes. It is a "lossy" type of image storage because even in its highest quality mode, there is Matrix Metering compression used to minimize its size. Matrix metering is a sophisticated process which reads light intensity from several points within the scene. The camera’s L metering system determines what “should” give your photograph proper exposure by Landscape Mode sampling the whole image and breaking it This is when you hold the camera in its into different sections to calculate the best normal, horizontal orientation to capture the exposure possible. This is the most accurate image. The opposite is "portrait mode". form of metering as it samples the whole scene and sets the exposure according to an Latitude average. The variance from "proper" exposure which will still provide acceptable results. Metering Metering is used to calculate the exposure LCD (Liquid Crystal Display) from the existing light conditions. Includes There are 2 types. First, a TFT high- Matrix Metering, Spot metering and Centre- resolution colour display device like a very weighted metering. small TV set. Secondly, a monochrome (B and W) information display using just black Mirror Lock Up alphanumeric characters on a grey or green Mirror lock-up (often abbreviated to MLU) is background. a feature employed in many Single Lens Reflex (SLR) cameras. It allows the operator LED (Light Emitting Diode) to reduce vibration-induced motion blur This refers to all the little red, green and during exposure. It also allows the mounting yellow indicator lights used on most of lenses which extend into the SLR's mirror cameras, power supplies and electronic box when mounted. devices. Moiré A visible pattern that occurs when one or more A light meter is a device used to measure halftone screens are mis-registered in a colour the amount of light. In photography, a light image. Often produces a coloured meter is often used to determine the proper checkerboard (or rainbow) pattern. exposure for a photograph. Typically a light meter will include a computer, either digital Motion Blur or analogue, which allows the photographer Motion blur is the apparent streaking of to determine which shutter speed and f- rapidly moving objects in a still image or a number should be selected for an optimum sequence of images such as a movie or exposure, given a certain lighting situation animation. It results when the image being and film speed. recorded changes during the recording of a

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Glossary of Photographic Terms

single frame, either due to rapid movement Neutral Density (or ND) Filter or long exposure. A neutral density filter or ND filter can be a colourless (clear) or grey filter. An ideal Motion JPEG neutral density filter reduces and/or modifies A video clip composed of a sequence of JPEG intensity of all wavelengths or colours of compressed images. Sometimes abbreviated light equally, giving no changes in hue of to MPEG (see MPEG below), although they are colour rendition. The purpose of standard slightly different. The main difference is that photographic neutral density filters is to MPEG provides temporal compression, while allow the photographer greater flexibility to MJPEG simply provides spatial compression. change the aperture, exposure time and/or motion blur of subject in different situations MOV and atmospheric conditions. Neutral density Apple QuickTime Movie file format. filters are often used to achieve motion blur effects with slow shutter speeds Movie Clip A sequence of motion captured in AVI, MOV or Noise MPEG formats. More and more digital cameras Relates to pixels in your image that were can now capture short movie clips, many can misinterpreted. Normally occurs when you also record the sound. shoot a long exposure (beyond 1/2-second) or when you use the higher ISO values from 400 MP or above. It appears as random groups of red, Abbreviation of Megapixel, such as in 5MP or green or blue pixels. Programs such as Neat 8MP. Image can remove most noise from an image.

MPEG Noise Reduction Motion JPEG movie file. The digital video Some cameras that offer long shutter speeds compression standard agreed upon by the (more than 1 second) usually have a noise Motion Picture Expert Group from the motion reduction (NR) feature that is either automatic picture computer industry. or can be enabled in the menu. This is to help eliminate random "hot" pixels and other image MPEG-EX noise. Can add more time to the process as it Motion JPEG movie file created by Sony needs to write the new image data along with cameras. This was the first motion video the recorded image. recording sequence mode that was limited in length only by the amount of available storage space. O

Multi-Pattern Metering OIS Exposure is determined by reading many Optical Image Stabilization, part is a family of different zones in the frame. This gives a more techniques used to reduce blurring. optimum exposure than those cameras using just a central zone metering system. Optical Viewfinder An eye level viewfinder that is used to Multi-Point Focusing compose the photograph. The autofocus systems uses several different portions of the image to determine the correct Optical Zoom focus. Means that the camera has a real multi focal length lens, this is not the same as a "Digital Multi Zone Focusing Zoom" which magnifies the centre portion of Many digital cameras now offer multi zone the picture. Optical zoom gives better quality focusing. The camera will automatically than a digital zoom. determine which zone (centre, left, right, upper or lower) to use to perform the auto Orientation Sensor focusing. You no longer have to make sure A special sensor in some cameras that can tell that your subject is in the centre of the when you turn the camera round to portrait viewfinder in order to be correctly focused. orientation to take a vertical shot. It also tells the camera to display it that way later when viewed on a monitor or TV screen during N playback.

ND Overexposure Neutral Density. A neutral-grey pre-lens This is an image that appears much too bright. filter to reduce overall brightness without The highlights and colours are totally lost and altering colour balance. usually unrecoverable even by top software. Either the shutter speed was too long or the NEF (Nikon Electronic Format) aperture was too wide. The Raw image data file format used by the Nikon DSLR (D2x, D100, etc) also some Coolpix digicams.

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Glossary of Photographic Terms

telephoto focal lengths. P (Polarizing Filter) A filter for eliminating glare and reflections Panning is the horizontal movement of a which attached to the front of your lens camera as it scans a moving subject. When (normally just SLRs). There are 2 types of panning, the camera is moved in polarising filter, linear and circular. Linear is synchronicity with the subject as it moves for film only, it screws up most auto focus parallel to the photographer. To pan systems on digicams. Therefore be sure you successfully, the camera follows the use a circular polarizer filter. It can also be subject’s movement and matches its speed used to darken skies and increase the and direction as closely as possible. saturation of colours.

Panoramic Photography PNG (Portable Network Graphics) Panoramic photography is a technique of This is an image file format. It is a photography, using specialized equipment or compressed file format similar to JPG. software that captures images with elongated fields of view. It is sometimes known as wide format photography. The In film and photography, a prime lens is term has also been applied to a photograph either a photographic lens whose focal length that is cropped to a relatively wide aspect is fixed, as opposed to a zoom lens, or it is ratio. the primary lens in a combination lens system. Parallax An effect seen in close-up photography where the viewfinder does not see the same R as the lens. This is normally due to the offset of the viewfinder and lens. This is not an Rangefinder issue if you are using the LCD as a This is the viewfinder on most smaller digital viewfinder or if your camera is an SLR. cameras and is a separate viewing device which is independent of the lens. It is often Partial Metering above and to the right or left of the lens. It This mode meters a larger area than spot exhibits a problem known as parallax when metering (around 10-15% of the entire trying to frame subjects closer than five feet frame), and is generally used when very from the camera so it is advisable to use the bright or very dark areas on the edges of the colour LCD when shooting close-ups for just frame would otherwise influence the this reason. metering unduly. Like spot metering, some cameras can use variable points to take RAW readings from, (in general autofocus points), RAW files store the unprocessed image data or have a fixed point in the centre of the at 12 bits per channel, directly from the viewfinder. Partial metering is found mostly camera's imaging chip to its memory storage on Canon cameras. device. "Lossless" compression is applied to reduce the file size slightly, without Control Lens (or Shift compromising the quality. RAW image files Lens) must be processed with special software A perspective control lens allows the before they can be viewed or printed. These photographer to control the appearance of are normally in the form of a plug in for perspective in the image; the lens can be Photoshop or as a standalone product. The moved parallel to the film or sensor, advantage is that you have the ability to providing the equivalent of corresponding alter the white balance, exposure value, movements. This movement of colour values, contrast, brightness and the lens allows adjusting the position of the sharpness as you see fit before you convert subject in the image area without moving this data into the standard JPEG or TIFF the camera back; it is often used to avoid format. Professional digital photographers convergence of parallel lines, such as when import RAW image data directly into photo- photographing a tall building. Lenses that editing programs like Photoshop CS (which provide only shift may be called shift lenses, comes with a Camera Raw plug-in that while those which can also tilt may be called works with most popular RAW formats.) tilt-shift lenses. The terms PC and TS are also used by some manufacturers to refer to Red-Eye this type of lens. An effect caused by an electronic flash reflecting off the retina at the back of the Photography eye making it look red. Compact cameras From the Greek, meaning "painting or with the flash located close to the lens suffer writing with light." the worst from this problem. Professional photographers use a bracket to hold an Pin-Cushioning external flash unit above and off to the side This is a common geometric lens distortion of the lens to eliminate red-eye. It can also causing an acquired image to pucker toward be easily reduced using most post-editing the centre of the image, usually found at software.

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Glossary of Photographic Terms

Red-Eye Reduction Mode A special flash mode whereby a pre flash or S a series of low powered flashes are emitted before the main flash goes off. This causes Saturation the iris of the eye to contract meaning less The degree to which a colour is undiluted by light gets in the eye, therefore reducing red white light. If a colour is 100 percent eye. saturated, it contains no white light. If a colour has no saturation, it is a shade of grey. Render This is the final step of an image transformation or three-dimensional scene Self-Timer through which a new image is refreshed on Pre-set time delay (e.g. 2, 5, 3, 5 or 10 the screen. seconds) before the shutter fires automatically. This allows the photographer be in the picture Resize without using a long cable release or remote In photographic terms, this means to take a control. It is also great for taking macro or large image and reduce it in size. Most night shots as by not touching the camera, you editing programs offer a resize option. eliminate the chances of camera shake. Is also good to use the "mirror lock up" function if you Resolution have it. The quality of any , whether printed or displayed on a screen, depends on Sepia its resolution, or the number of pixels used The (brownish) mono toned effect seen in to create the image. More, smaller pixels add images from the original 19th and early 20th detail and sharpen the edges. Optical Century cameras. This is now a feature often Resolution is an absolute number that the found as a special image effect on some camera's image sensor can physically record. digicams and/or editing software. Interpolated Resolution adds pixels to the image using complex software algorithms to Shutter determine what colour they should be. It is The physical device that opens and closes to important to note that interpolation doesn't let light from the scene strike the image add any new information to the image - it sensor. Digicams use both electronic and just makes it bigger mechanical shutters.

RGB (Red, Green and Blue) Shutter Lag The primary colours from which all other The time between pressing the shutter and colours are derived. The additive actually capturing the image. This is due to the reproduction process mixes various amounts camera having to calculate the exposure, set of red, green and blue to produce other the white balance and focus the lens. It is colours. Combining one of these additive worse with smaller digicams whereas the colours primary colours with another better DSLR's now have little or no shutter lag, produces the additive secondary colours like the better film SLR's. cyan, magenta and yellow. Combining all three produces white. Shutter Priority and Shutter Priority AE When the photographer selects the shutter speed and the camera automatically sets the The rule of thirds is a "rule of thumb" or corresponding aperture determined by lighting guideline which applies to the process of conditions. Shutter speed priority is used to composing visual images such as paintings, control motion capture. A fast shutter speed photographs and designs. The rule proposes stops fast action, a slow shutter speed blurs a that an image should be imagined as divided fast moving subject. It is good to use shutter into nine equal parts by two equally-spaced priority for sports or . horizontal lines and two equally-spaced vertical lines, and that important compositional Shutter Speed elements should be placed along these lines or How fast the camera's shutters open. It their intersections. Proponents of the determines how long the film is exposed for. technique claim that aligning a subject with these points creates more tension, energy and Skylight Filter interest in the composition than simply This is an Ultra Violet absorbing filter that cantering the subject would. helps overcome the abundance of blue in outdoor photographs. Not really necessary in digital photography as the camera's white balance system adjusts for the colour temperature of the scene. You can also use them to protect the camera's lens from scratching, fingerprints or dirt.

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Glossary of Photographic Terms

SLR (Single Lens Reflex) TLR This means the camera has one lens (as Twin-Lens Reflex, a camera with two lenses, opposed to Twin Lens Reflex like the Rolleiflex) one for taking pictures and one for viewing that involves a mirror and prism that the the scene. The two lenses are typically linked viewer looks through (as opposed to a point to ensure that they remain focused at the and shoot or rangefinder where the viewer same distance. looks through a separate viewfinder. TTL Spot Metering Through-the-lens; commonly used when With spot metering, the camera’s auto referring to metering through the lens as exposure system will only measure a very opposed to via a separate meter. Effective small area of the scene (between 1-5% of for fill-flash and other tricky lighting the viewfinder area). This will typically be situations the very centre of the scene, but some cameras allow the user to select a different Twain (Technology Without An Industry off-centre spot, or to recompose by moving Name) the camera after metering. Protocol for exchanging information between applications and devices such as scanners Stitching and digital cameras. TWAIN makes it Combining a series of images to form a larger possible for digital cameras and software to image or a panoramic photo. It requires communicate with each other on PCs. special post editing software.

Sunny 16 Rule U In photography, the Sunny 16 rule (also known as the Sunny f/16 rule) is a method of Under Exposure estimating correct daylight exposures without This happens when a picture appears too a light meter. Apart from the obvious dark because insufficient light was delivered advantage of independence from a light meter, to the imaging system. It is the opposite of the Sunny 16 rule can also aid in achieving over exposure. correct exposure of difficult subjects. As the rule is based on incident light, rather than USM (Canon) reflected light as with most camera light UltraSonic Motor - Canon's fastest, quietest meters, very bright or very dark subjects are autofocus lens mechanism. compensated for. The rule serves as a mnemonic for the camera settings obtained on UV Filter a sunny day using the exposure value (EV) This is an Ultra Violet absorbing filter that system. helps overcome the abundance of blue in outdoor photographs. Not really necessary in digital photography as the camera's white T balance system adjusts for the colour temperature of the scene. It can be used to TCon protect the camera's lens from scratching, Telephoto converters for increasing focal fingerprints or dirt. length. UXGA Telephoto This refers to an image resolution size of This is the focal length that gives you the 1600 x 1200 pixels. narrowest angle of coverage, good for bringing distant objects closer. (i.e. 100mm, 200mm, 500mm etc.). V, W, X and Z

Thumbnail VGA A small, low resolution version of a larger Refers to an image resolution size of 640 x image file, which is used for quick identification 480 pixels. or speedy editing choices. Viewfinder TIFF (Tagged Image File Format) In photography, a viewfinder is what the An uncompressed image file that is lossless photographer looks through to compose, and and produces no artefacts as is common with in many cases to focus, the image. Most other image formats such as JPEG. viewfinders are separate, and suffer parallax, while the single-lens reflex camera lets the Time-Lapse viewfinder use the main optical system. Capturing a series of images at pre-set Viewfinders are used in many cameras of intervals. Also known as Interval Recording or different types: still and movie, film, Intervalometer. analogue and digital. A zoom camera usually zooms its finder in sync with its lens, one exception being rangefinder cameras.

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Glossary of Photographic Terms

Vignetting The term that describes the darkening of the Further outer edges of the image area due to the use Important Notice of a filter or add-on lens. Most noticeable Information © Copyright 2019, Martin Pollins, when the zoom lens is in full wide-angle. It is This guide is for general interest - it is All Rights Reserved also sometimes used as a special effect in the photo editing stage of development. always essential to take advice on This publication is published by specific issues. We believe that the Bizezia Limited. It is protected by White Balance facts are correct as at the date of copyright law and reproduction in This refers to the adjustment of the publication, but there may be certain whole or in part without the brightness of the red, green and blue errors and omissions for which we publisher’s written permission is components, so that the brightest object in strictly prohibited. The publisher the image appears white. See also "AWB" cannot be responsible. may be contacted at [email protected] Wide angle The focal length that gives you the widest Some images in this publication are angle of view. I.e. 10mm, 16mm, 24mm taken from Creative Commons – etc. such images may be subject to copyright. Creative Commons is a WR non-profit organisation that enables Weather Resistant (mainly Pentax brand). the sharing and use of creativity Cameras and lenses with waterproof seals. and knowledge through free legal tools. XGA This refers to an image resolution size of Articles and information contained 1024 x 768 pixels. herein are published without responsibility by us, the publisher Zoom Lens or any contributing author for any A variable focal length lens. The most loss howsoever occurring as a common on digicams has a 3:1 ratio (i.e. consequence of any action which 35-105mm). Detachable zoom lenses include you take, or action which you for example, 24-70mm, 70-200mm and 100- choose not to take, as a result of 400mm. this publication or any view expressed herein. Whilst it is believed that the information contained in this publication is correct at the time of publication, it is not a substitute for obtaining specific professional advice and no representation or warranty, expressed or implied, is made as to its accuracy or completeness.

The information is relevant within the United Kingdom. These disclaimers and exclusions are governed by and construed in accordance with English Law.

Publication issued or updated on: 20 February 2012

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