Photography - Glossary

Photographic Encyclopaedia

Digital Photography Terms from Aperture to Zoom lens

This Photographic Glossary Offers Simple,
Jargon-free explanations of digital photography terms from Aperture to Zoom lens

Common Photographic Glossary that you may have heard of:


The inability of a lens to produce a perfect, sharp image, especially at the edge of the photo.
(see Barrel distortion & Pincushion effect )

Accessory shoe
Metal fitting on the top of a camera which supports the flash gun, also various other accessories such as a viewfinder or rangefinder.
(see Hot Shoe, Finder & Rangefinder)

A term which describes a lens system which is corrected for chromatic aberration.
(see Chromatic Aberration)

Keeping a chemical moving: Agitation helps to speed-up and achieve an even development while processing film or paper. It also prevents spotting or staining by keeping the developer, stop bath, or fixer in motion.

Ambient Light
The available light. Already existing in an indoor or outdoor setting which is not caused by any illumination created by the photographer.
(see Existing light )

Instrument used in photo printing to determine correct colour filtration (colour balance) when making colour prints. (see Colour Balance)

Angle of coverage
Concerning Large Format lenses: The maximum image area of usable quality which a certain lens can produce (the image circle). Known as the angle of coverage.

Angle of view
Angle of view is determined by the focal length of the lens. A wide-angle lens includes more of the scene than a normal (standard lens) or telephoto lens.
(see Standard lens,Tele & Wide )

The opening in a lens through which light passes to expose the film. Aperture size is usually calibrated in f-numbers, the larger the number, the smaller the lens opening, therefore the slower the shutter must be!
(see f-stop)

Apochromatic (APO lens)
Lens corrected for chromatic aberrations in all three primary colours. Many manufactures use different names (i.e. NIKON use ED)

Introduced in 1996 the Advanced Photo System (APS) was devised by a group of five manufactures: Canon, Fuji, Kodak, Minolta and Nikon as a 'breakthrough in camera and film technology' and created a new generation of 'point-and-shoot' cameras. Now, with hindsight, just an interim consumer product which just filled a gap until the more innovative compact digital cameras became affordable. The film size is smaller than 35mm.
(see 35mm)

Unwanted digital image degradation (file compression) caused by errors or limitations during capture or created while processing, storage or transport.
(see JPEG, Lossy)

Artificial light
Light not originating from a natural source. The commonest artificial light sources in photography are flash, and tungsten bulbs.
(see Tungsten light)

ASA (American Standards Association)
An old film speed rating system. Now superseded by ISO.
(see ISO)

Aspect Ratio
The ratio of width to height in an image. Wide-screen TV 16x9 and traditional TV 4x3. Still photography offers many aspect ratios, from square format (such as 6x6 cm) to various panoramic formats.
(see Format)

Available light
(see: Existing light )

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B ("Bulb")
Shutter setting on which the shutter will stay open as long as the release is depressed. Used for exposures longer than the numbered shutter speed settings.
(see Shutter speed)

Back focusing
The tendency of a lens to focus slightly behind the intended subject.
(see: Front focusing)

Light from behind the subject, and towards the photographer, so that the subject stands out against the background. This sometimes can produce a silhouette effect.

Background paper
Available in numerous colours, the rolls are hung from the ceiling or a set of free standing poles. The common sizes are 9ft and 4ft 6ins wide.
(see Cove)

Bag bellows
Used on large format cameras in place of normal bellows when wide-angle lenses are in use. (A flexible "bag" affair)
(see Bellows, Large format & Wide )

Balanced Fill Flash
When a modern camera with a multi-segment exposure meter (Matrix) is used with a dedicated flashgun the correct exposure can be obtained for both the subject and background using 'Automatic Balanced Fill Flash' in both daylight and low light. Balanced Fill Flash can also be achieved manually using a little knowledge and technique.
(see Matrix & Dedicated flash, Syncro Sun)

Barn doors
Accessory used on lights to control the direction of output and the width of the beam.

Barrel distortion
Lens aberration (distortion) where straight lines are formed as curved lines in the image. These barrel shaped lines are most noticeable along the edges of the photo.
(see Aberration & Pincushion effect )

Baseboard camera
Portable large format camera supported on a baseboard. It only gives limited use of the camera movements.
(see Camera movements, Field camera & Technical)

A set of numbers and letters printed on the packaging of film and paper to indicate a production batch. The number is given because of slight variations of colour, contrast and speed which may occur between batches of the same type.

All modern 35mm SLR cameras now use a "bayonet" lens fitting (a quarter turn clockwise or anti-clockwise will remove or attach the lens). Each camera manufacturer has its own type of fitting, therefore as an example a Canon lens cannot be attached to a Nikon camera body.
(see Screw mount lens, 35mm & SLR)

Large format cameras: The folding (piano accordion style) part that connects the standards (lens and film back). Also a camera accessory for smaller formats that aids close focusing.
(see Monorail & Standard)

Between-the-lens shutter
Close to the diaphragm, inside the lens are metal blades which spring open and then close when the camera is fired, this exposes the film or image sensor
(see Focal plane shutter)

A single unit of digital information. Using binary notation a single bit has a value of either zero or one.

Bit Depth
The amount of colour information associated with a digital image. An image with a higher bit depth can display more gradations of colours. The most common colour bit depth for digital photos (especially jpeg files) is 8 bits per colour, (a 24-bit RGB image). Professional digital cameras capture 16 bits per colour when shooting RAW files.
(see RAW)

A digital image created from rows and columns of dots called pixels, the more bits associated with each pixel, the higher the bit depth. Bitmap occasionally refers specifically to images in which the dots are either pure black or white with no shades of gray and the image can be represented with one bit per pixel.
(see Bit Depth & Pixel)

Bleach fix
Chemical bath in which bleach and fixer have been combined! Used in many Traditional colour processes.
(see C41 & E6)

A Type of Tungsten Lighting from various manufactures, rated at 2000W.
(see Redhead & Tungsten light )

Bokeh describes the rendition of out-of-focus points of light. Differing amounts of spherical aberration alter how lenses render out-of-focus points of light, and thus their bokeh. The word "bokeh" comes from the Japanese word "boke" (pronounced bo-keh) which literally means fuzziness or dizziness.

For a full description go to http://www.kenrockwell.com/tech/bokeh.htm
(see: aberration)

Flash or tungsten light bounced off a reflector (such as the ceiling, walls or brolly) to give the effect of natural light.
(see Brollies)

The technique of taking a number of pictures of the same subject at different levels of exposure. At half and one stop differences, depending on subject.
(see f-stop)

Bridge camera
A term to describe a camera that fills a gap between SLR and compact cameras. Can be similar in size and weight to a SLR, but lacks interchangeable lenses. Originally devised in 1988 by Ricoh with the Mirai (also sold as the Olympus AZ-4 Zoom SLR). Today the 'Bridge' has more competition from other types of cameras filling the same niche, particularly from the Micro Four Thirds system.

'this class of cameras can be a "bridge" towards finally switching to an SLR system.' http://camera-wiki.org/wiki/Bridge_camera
(see: SLR, Compact camera & Micro Four Thirds system)

Photographic white or silver Umbrellas! used to bounce flash light off of.
(see Bounce)

(see Bromide paper)

Bromide paper
Photographic printing paper which is coated with a light sensitive emulsion of silver bromide, to reproduce traditional black and white images.
(see: Emulsion, Fibre (FB) and RC paper)

Memory in a digital camera that stores the photos before they are written to the removable storage card.
(see Compact Flash)

Bulk film
Film purchased in long lengths and used in a bulk camera back, in assignments which demand a large amount of film in long continuous runs, (or with a bulk film loader, to reload cassettes cheaply).

Bulk back
A device that allows the use of many many feet of film at one loading: 35mm or 70mm (medium format). (see Bulk film, Medium format & 35mm )

A photo is said to be burned when it contains uniform portions of black or white where there should be detail. Overexposed descriptions: washed out, blown out highlights or clipped whites. Underexposed descriptions: loss of shadow detail, muddy, indistinguishable from black, blocked up shadows, crushed blacks or clipped blacks
(See Over exposed & Under exposed)

Burning-in (or Burn-in)
To make an area of a print darker. This is accomplished after the basic exposure by extending the exposure time (or opening the aperture) to allow extra image-forming light to darken areas of the print while holding back the light from the rest of the image (with hands or card etc.); also called printing-in.
(see Dodging & Exposure )

A unit of digital information most often consisting of eight bits. File sizes and storage capacities are commonly described in thousands of eight-bit bytes (kilobytes), millions (megabytes), billions (gigabytes) or trillions (terabytes).
(see Bit)

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The number given to a Chemical process for developing colour negative film. (created in 1972 by Kodak but adopted universally by every other manufacturer).

Cable release
Flexible cable for firing a camera shutter. Useful for long exposures where touching the camera release by hand could cause camera-shake blur.
(see Exposure Shutter & Shutter speed)

Camera Format
The size and aspect ratio of an image produced on film or digitally. Large format, medium format, or 35mm, but determined by the actual dimensions of the focal plane or image sensor. Digital capture technologies are confusing the traditional distinctions, since a small image sensor with many pixels is not necessarily better in quality than a larger sensor with less pixels.
(see Format, Large format, Medium format, Pixel & 35mm)

Camera movements
Mechanical Systems most common on large format cameras (and some Medium Format) which provide the facility for lens and film plane movement from a normal standard position. The movements can create greater or lesser depth of field, and correct or distort image shape.
(see Depth of field, Movements & Standard)

Camera obscura
For hundreds of years the camera obscura was a curiosity, consisting of a darkened room with a small hole in one of its walls; a reduced inverted image of the world outside was projected through the hole onto a whitewashed wall opposite; the phenomenon was noted by the Arabs as early as the eleventh century.
By the end of the sixteenth century Italian academics had fitted a converging lens into the hole which produced a much brighter and sharper picture. Artists began to use a collapsible, portable version to reproduce perspective in their landscapes and portraits.
(see Pinhole camera)

(see Colour Balance, Colour Cast & Colour correction)

Catadioptric lens
(see Mirror lens)

CC filter
Abbreviation for colour compensating filter. CC filters are designed primarily for correcting colour bias in colour photo printing. CC2OY, for example, indicates a yellow filtration of 0.2 density.
(see Colour correction)

Charge Coupled Device (CCD). The Digital camera's 'film'; a CCD converts light into a digital photograph of pixels. When a picture is taken the CCD is struck by light coming through the camera's lens; each of the millions of tiny pixels that make up the sensor converts this light into electrons.
(see CMOS & Pixel)

CD ROM (Compact Disc)
Read only memory/media: an electro-optical data storage medium with the same physical format as an audio disc and a capacity of approximately 650-700mb of data.
(see: Megabyte)

Centre Weighted
A camera metering system which concentrates the light reading mostly to the central portion of the viewfinder and feathering out to the edges. Although in the hands of an inexperienced photographer a 'Matrix' style meter will achieve more correct results many professionals still prefer to use their cameras in manual mode with the meter set to 'centre weighted'! Now regarded as a 'classic', this metering system is included in all quality 35mm SLR's and DSLR's.
(see Matrix, finder, 35mm & SLR)

CF Card
(see Compact Flash)

Changing bag
A light tight fabric bag, used for safely removing sensitive photographic materials from film holders or backs in daylight.

Chromatic Aberration
The inability of a lens to focus different colours on the same focal plane. Appearing as a 'colour fringe' around objects, especially at the edges of the photograph.

A positive transparency designed to be viewed when lit from behind. Used frequently to describe a 'positive' camera film. Large chromes are used for advertising or promotion purposes, and are sometimes known by the kodak brand name duratrans ‘durable transparency’.
(see E6, Trannie & Transparency)

Chromogenic film
Chromogenic literally means 'colour forming'. In chromogenic films the final image is made of coloured dyes formed during processing rather than Silver Halide. A Black & White chromogenic film can be processed along side colour films in a C41 process.
(see C41 & Silver Halide)

Circle of confusion
Disc of light in the image where a point on the subject is not perfectly brought into focus. The eye cannot distinguish between a very small circle of confusion and a true point.

"Clean & tight"

A phrase often used by photographers when describing a well composed (clean) photo which eliminates all inconsequential items from the photo (tight).

Clearing time
"Twice the clearing time" is a popular darkroom term.
Insufficient time in the fix causes film to appear milky. Photographers use a film clipping in the fixer chemical to accurately time this process, after a second clipping is 'clear' the film is ready for washing.
(see Fix)

Clip test
A test to determine accurate development times using a small part of the exposed film as a sample.

Close-up lens
A lens attachment used in front of the camera lens; pictures then could be taken at a closer distance than normal.
(see Extension tubes & Macro)

Complementary Metal-Oxide Semiconductor (CMOS). An image sensor used in some digital cameras. Its basic function is the same as the CCD.
(see CCD)

(see Multicoating)

Colour balance
How a particular colour film reproduces the colours of a scene. All Colour films are formulated to be exposed by light of a certain colour quality (daylight or tungsten). It also describes an adjustment in colour photo processes that ensure a neutral scale of grey tones is reproduced accurately, i.e. a grey subject will have no colour cast or bias.
(see Daylight film & Tungsten film)

Colour cast
Overall bias towards one colour in a photograph.
(see Colour Balance)

Colour correction
Filters which help balance the colour rendition of a scene to match the colour response of the eye.
(see CC filters)

Colour Gamut
The complete set of colours found within an image. Printing an image requires transforming the photo from the original RGB color space to the printer's CMYK colour space. This process converts the colours from the RGB which are out of gamut to approximate values within the CMYK space gamut.

Colour Management System
A system for communicating colour reproduction information about digital images between input, display and output devices.
Improves fidelity of image reproduction when properly configured by all involved in a production workflow.

Colour Profile
Colour space information can improve colour fidelity when embedded into a digital image file and referenced within a 'Colour Management System' reproduction workflow.

Colour sensitivity
The response of a sensitive material to the colours of the spectrum

Colour Space
A three-dimensional representation of a colour profile, useful in digital imaging to understand colour performance between input, display and output devices.
(see: Colour Management System)

Colour temperature
Measured in Kelvin, expressed on a scale (i.e.3400K) this indicates the colour content and quality of a light source light such as a lamp.
(see Tungsten film)

A lens defect which results in points of light appearing in the image not as points but as discs with comet-like tails.

Compact camera
A small camera that is both easy to use and also small enough to carry in a jacket pocket or hand bag.
(see: Point and Shoot)

Compact Flash
The removable CF card is a popular Digital Camera photo storage system. Although they are larger than SD, Smart Media, XD Picture Card and Memory Sticks 'Professional' use has made them widely available and in very large sizes, currently up to 128 Gigabytes.
(see Memory Stick, Micro Drives, SD, Smart Media & XD Picture Card)

Complementary colour
The hue most opposite to a given colour. The complementaries for blue, green and red are yellow, magenta and cyan respectively.

The act of combining two or more images. Today usually accomplished digitally using 'Photoshop'.
(see Photoshop)

Compound lens
Lens system consisting of two or more elements.

A digital file is compressed by removing redundant information. Some image file compression methods discard visual information that may degrade image quality.
(see JPEG and Lossy)

Compression Ratio
The amount of data in a digital image divided by the amount of data in a version after compression. Higher ratios indicate more compression which may degrade image quality.
(see JPEG and Lossy)

Concave lens
Simple lens, or lens shape within a compound lens, whose surfaces curve inward. Such a lens causes light rays to diverge.
(see Compound lens)

A simple lens system which concentrates light from a source into a beam. Condensers are used in equipment such as slide projectors, spotlights and enlargers.
(see Focusing Spot)

Contact print
A print made from placing the negative in 'contact' with a sheet of photo paper and then exposed to light; the resulting "Contact print" is the same size as the negative and therefore not enlarged.
(see Contact printer & Enlargement)

Contact printer
Apparatus used for making contact prints. Usually just a simple frame with a glass top to hold the negative and paper in tight contact during exposure.

A subjective judgment of the difference in brightness and density between shadow and highlight areas in an image. Contrast is affected by lighting, lens flare, film type, degree of development, enlarger type and quality of printing.

Contrast grade paper
Graded by numbers (usually 1-5), the contrast grades of Black & White photographic papers, enable us to obtain good prints from negatives of varying contrasts. Use a low-numbered or soft paper with a high contrast negative to get a print that most closely resembles the original scene. Use a high-numbered or a hard paper with a low-contrast negative to obtain a normal contrast print.
(see Multigrade)

Higher-than-normal contrast including very bright and very dark areas. The range of density in a trannie or print is higher than it was in the original scene.

Converging angles
This occurs when the camera is not held or supported vertically. The vertical lines will seem to run together at the top or the bottom of a photo. Most noticeable with photographs of tall buildings.
(see Movements, Rising front, Keystoning & Shift)

A supplementary lens that can double the length of a telephoto lens (e.g.: 2x converter). Usually fitted between lens and camera body.

Convex lens
Simple lens, or lens shape within a compound lens, whose surfaces curve outward. Such a lens causes rays of light passing through it to converge.
(see Compound lens)

Not an original. A print, neg., trannie, artwork or 2D object copied on a copystand
(see Copystand & Dupe).

A legal property right in an original work of any physical medium of expression, such as photographs. Copyright is more than the right to copy, the owner of copyright holds the exclusive right to reproduce, publicly display, adapt, distribute and to authorize others to do the same.

A device that holds a 2D object square with the camera to obtain quality copies of an original, the stand usually has lights attached.

Correction filter
A filter which alters the colour rendition of a scene to suit the colour response of the eye.
(see Colour correction)

Coupled rangefinder
Focusing system in which a rangefinder and the lens focusing mechanism are linked. As the lens is adjusted, the central area of the viewfinder indicates when the lens is in focus (as found on Leica M series Cameras).

Infinity cove. Found in most large studios and painted white, a solid background that wraps over the floor & walls to create the illusion of an infinite 'white'.
(see Background paper)

Covering power
The maximum area of usable image quality which a lens will produce. Known as the angle of coverage. (Frequently a required knowledge when using a large format camera with "movements").
(see Movements)

Printing or using only part of the image that is in the original negative or trannie, usually for a more pleasing composition. Could also refer to the framing of the scene in the viewfinder.
(see Clean & Tight)

Cross process
To develop a film in the wrong process (e.g.: neg.(C41) film in trannie(E6) chemicals) to obtain a sometimes bizarre colour or contrast effect.
(see C41& E6)

Curvature of field
Lens aberration causing the plane of sharp focus to be curved.
(see aberration)

Cut film
Large format film available in flat sheets. The most common are in "Imperial sizes": 4 ins x 5 ins and 8 ins x 10 ins .
(see Large format)

Cyclo wall
A cyclo wall, also referred to in various combinations as: infinity, seamless, cyc, cyclo, wall, drop, backdrop and background. A curved wall used as a background of a stage set to suggest unlimited space.
(see Cove)

A large curtain or wall, often concave, positioned at the back of a Theatrical stage. As the name implies, it often encircles or partially encloses the stage to form a background.
(see Cyclo wall)

A colour system based on the four colours used in colour printing: Cyan, Magenta, Yellow and BlacK. Can also be a colour mode used to define colours in a digital image. All Digital cameras & scanners are RGB devices, a colour method based on combinations of the primary colours Red,Green & Blue this is the same as your TV and PC monitor. CMYK is primarily used when preparing digital images that will be printed using the process colours by a printer or publisher on a four colour printing press.
(see RGB)

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Dark slide
Light-tight film holder for large format cut film.

Cloth made of a dark material and placed over the Photographer's head and camera back to help the viewing and focusing of images on the ground glass screen of a Large format camera.

A photographer's eight-hour work period. "That shoot will require a full day."

Day Rate
A pre-agreed, flat-rate photographer's fee, paid for up to one day of photography. Generally based on an 8-hour day.

Daylight film
Film balanced to a colour temperature of 5400K which will give a natural result with 'daylight' and also 'flash'.

Daylight tank
A light-tight container for film processing. Film is loaded in the dark after which all other processing steps can be carried out in normal light.

Dedicated flash
A flashgun designed for use with a specific camera. It links directly with the internal camera circuitry to help produce perfectly exposed photos.

The blackness of an area in a negative or print. Sometimes referred to as contrast.
(see Contrast)

Depth of field
The distance between the nearest and farthest objects that appear in acceptably sharp focus in a photograph. Depth of field depends on the lens aperture, the focal length of the lens, and the distance from the subject.
(see Aperture & Focal length)

Depth of focus
Very narrow zone on the image side of the lens within which slight variations in the position of the film will make no appreciable difference to the focusing of the image.

Dev. (Developer)
A Chemical bath which converts exposed silver halides to black metallic silver, so making the latent image on exposed films or photographic papers visible.
(see Latent image)

Developing Tank
A light tight container used for processing film.
(see Daylight tank)

The device, usually found inside the lens, which uses a set of interleaving blades to control the size of the aperture.
(see Aperture)

Diffuse Lighting
Lighting that is low or moderate in contrast; an overcast day is a good example.

Any material capable of letting light scatter (diffuse) through it.

Popular term for a Digital camera. A camera that does not use traditional silver halide film.
(see Silver Halide)

Digital Asset Management System
A database program designed for tracking and organizing digital files, including documents, images, video etc. Usually the program also allows metadata to be added.
(see Metadata)

Digital Negative
Similar to a RAW file but an open format that does not need manufacturer-specific software, although a digital negative still requires processing before it can be used. Capable of delivering more colour and dynamic range than a TIFF or JPEG digital image file. Adobe 'dng' is a Digital Negative.
(see RAW, JPEG & TIFF)

Digital SLR
A digital SLR is simply a SLR camera that takes photos digitally (electronically) rather than using traditional film; popular examples are the Nikon D7100 and Canon EOS 60D.
(see SLR)

DIN (Deutsche Industrie Normen)
The German industrial standard for rating film speed. This scale indicates a doubling of speed by an increase of 3 in the rating; a rather complicated standard, it fell from widespread use during the early 'Seventies' although the late German manufacturer Agfa carried on using the system for film identification until more recently.
(see ISO)

Close-up lenses (which screw into the front of an existing lens and act like a reading glass) are often marked in "diopters" (2.5 diopter close-up lens) The diopter value of a lens is calculated by taking the reciprocal of the focal length expressed in meters. Each diopter is the number of times the focal length of the lens will divide into one meter

There are various lens induced 'distortions' that can effect the photographic image.
(see: Aberration , Barrel distortion & Pincushion effect )

'Local' control of density in photographic printing achieved by shading (using your hands, small pieces of card or various other dodging tools), therefore, holding back the image-forming light from a part of the photo to make that area of the print lighter.
(see Burning- in)

DPI (Dots Per Inch)
A measurement unit describing the resolution of hardware, such as a computer monitor or digital printer. Although strictly incorrect, it is now often used as the resolution unit for a digital image.

DSLR is a Digital SLR camera.
(see SLR & Digital SLR)

A duplicate of an original. Usually the term is used to describe a duplicate trannie.
(see copy)

DVD (Digital Versatile Disc)
A high-capacity, electro-optical data storage media. Initially capable of storing approximately 4.7gb. Recent revisions of the technology can store more. Some types can be erased and recorded again.
(see Gigabyte)

A Nikon Digital format. Some Nikon Digital SLRs have CCDs smaller than the area of a 35mm film frame therefore a DX lens will cause vignetting if used on a 35mm film camera. Used on a Nikon FX camera the format automatically switches to the smaller DX size.
(see Vignetting & FX)

DX code
An electrical system built into recent 35mm cameras to automatically adjust the camera for the correct film speed.
(see 35mm)

Dye sublimation
A printer that uses heat to transfer dye onto various types of medium material. Many consumer and professional dye-sublimation printers are designed and used for producing photographic prints. An advantage over inkjets is that prints are dry and ready to handle as soon as they exit the printer.
(see Ink Jet Print)

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The number given to a Chemical process for developing colour transparency film. (created by Kodak during the early 70's and adopted universally by every other manufacturer).

(Xerox), a dry photocopying technique invented by Chester Carlson in 1938, the invention was initially called electrophotography and was later called xerography. The same process can be found in modern Colour Laser or LED printers.

The light-sensitive material (which is suspended in micro-thin layers of gelatin) that is coated onto different bases to make photographic film, or paper.

A print larger than the negative or trannie used to produce it (blow up).

A popular autofocus 35mm SLR camera system made by Canon. "EOS" (Electro Optical System) is also the name of the goddess of dawn in Greek mythology. First introduced to the world in March 1987 with the EOS650 camera.
(see SLR & 35mm)

EF lens
The lens of the Canon EOS autofocus camera system.
(see EOS & Bayonet)

'Electro Selective Pattern' a Matrix style metering found in Olympus cameras.
(see Matrix)

E-TTL (Evaluative-Through The Lens) flash metering. A Canon EOS flash exposure system that uses a brief pre-flash before the main flash in order to obtain a more correct exposure.
(see Balanced Fill Flash & EOS)

Electronic Viewfinder Interchangeable Lens. Currently found in some Four Thirds system cameras. Electronics is used instead of an optical glass prism, the finder image quality is lower than a traditional SLR but has an advantage of reducing both size and weight.
(see Finder & SLR )

EXIF data
EXIF (Exchange image file format). This is a standard that allows information stored with the digital photograph (camera setting and exposure information) to be used to achieve a balanced colour when the photo is output on a EXIF data-compliant printer. Many programs can also read and display this information.

Existing Light
Available light, includes all natural lighting from moonlight to sunshine; and for photographic purposes, existing light is also the light that is already on the scene. Therefore it takes in: room lamps, fluorescent lamps, neon signs, candles, daylight through windows, and artificially illuminated night scenes.

The quantity of light allowed to act on a photographic material; the lens aperture controls intensity or amount of light, and the shutter speed (or the enlarger timer in printing) controls the time.
(See Aperture, Shutter speed & Over exposed )

Exposure compensation
To obtain the best results with certain subjects it may be necessary to alter the exposure from the value suggested by the camera. An exposure compensation button [+/-] is now found on most modern auto cameras. Positive compensation may be needed when the main subject is darker than the background and negative compensation may be needed for a subject lighter than the background.

Exposure latitude
The amount by which you can over or under expose a light-sensitive material with standard processing, and still achieve an acceptable result.

Exposure meter
A photographer's instrument for measuring the amount of light (available or flash) falling on or being reflected by a subject, and converting this measurement into usable information: shutter speed and f stop.
(see Existing light , f-stop & Shutter speed )

Extension tubes
Metal tubes added to 35mm or medium format cameras, to extend the lens film distance, enabling a magnification greater than x 1(life size).
(see: Close-up lens & Macro)

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f - Stop
A number that indicates the size of the lens opening . The common f-numbers on 35mm cameras are f1.4, f2, f2.8, f4, f5.6, f8, f11, f16, and f22. The larger the f-number, the smaller the lens opening, f22 is the smallest in this series. Also called the aperture, they work in conjunction with shutter speeds to indicate exposure settings. The number sequence is printed on the lens barrel, each higher f number halves the exposure of the preceding one.
The f-number itself is effectively the number of times the aperture diameter will divide into the lens focal length. For example, f4 aperture diameter is one quarter the focal length (i.e. 25mm aperture diameter in a 100mm focal length lens).
(see: Aperture)

Fast film
Film with an emulsion that is very sensitive to light. Such films have high ISO ratings (i.e.: ISO1600). They are all, however, more grainy than there slower counterparts.
(see Grain & ISO)

Fast lens
A lens with a wide maximum aperture (f2.8 is a fast lens in a 35mm telephoto design). Often used in low light situations or when a fast shutter speeds are always required.
(see Aperture, Shutter speed & Tele)

Fibre (FB)
Fibre based photo printing paper of a traditional type (no plastic). High quality if printed & processed well but takes a long time to wash and dry.
(see Bromide paper, Multigrade & RC paper)

Field camera
Type of folding Large format Camera usually made of wood, therefore lighter than a metal camera of the same type. Used in the "Field" for landscapes but can be used in the Studio as a alternative for a Monorail but with less "movements".
(see Baseboard, Monorail, Movements & Technical)

File Format
The form or type of file used in Digital photography and to store images and other information on computers. Some popular examples of file formats are TIFF, JPEG, psd and dng.
(see JPEG, TIFF and RAW)

File size
The size of an image in digital photography, measured in kilobytes (K), megabytes (MB), or gigabytes (GB). File size is proportional to its pixel dimensions; images with more pixels may produce more detail at a given printed size, but they require more disk space to store and are slower to edit, print and e-mail as an attachment.
(see Pixel & Image resolution)

Light from an additional lamp, flash, or reflector; used to soften or 'fill in' the shadows caused by the brighter main light, often the Sun. Called fill-in flash when flash is used.
(see Reflector)

Film back
Separate part of a Roll film Medium Format camera that holds the film. It aids speedy film change; especially with many preloaded backs or an assistant loading during a long session.
(see Medium format)

Film Speed
The sensitivity of a film to light, indicated by a number such as ISO 100. The higher the number, the more sensitive or faster the film. (ISO stands for International Standards Organization.)
(see Fast film, Slow film & ISO)

A piece of glass or other transparent material used over the lens which alters the nature, colour or quality of the light passing through it.
(see CC filters)

Also known as a viewfinder. A viewing aid in a camera, used for composing, and usually focusing the subject. It would normally also display exposure information in smaller formats.
(see Exposure & Focusing screen )

Fine Art
Description of photography that is intended for private or gallery display rather than reproduction. Created more for aesthetic appreciation than for commercial use.

Fish fryer
Type of lighting attachment (a large overhead light).

Extreme wide-angle lens with an angle of view exceeding 100 degrees and sometimes in excess of 180 degrees Depth of field is practically infinite. It produces highly distorted images.(Note: lines are not drawn square!)
(see Angle of view, Depth of field & Distortion)

Chemical process which converts unused light-sensitive silver-halide crystals to a soluble silver complex in both negatives and prints, making the image stable and unalterable in white light. Also referred to as hypo.
(see Hypo)

Non-image-forming light scattered by reflections within a lens or enlarger/camera interior which reduces image contrast and detail.
Flare can affect film by causing a lowering of image contrast.
(see Contrast, Distortion, Multicoating & Hood)

Flash range
The distance over which a flash unit can give adequate illumination.

Flash sync.(synchronization)
Method of making a flash light fire at the correct moment, exactly when the shutter is fully open. Normally a camera's flash sync. speed is quoted as the highest speed that a given camera can synchronize with a flash unit (e.g.:1/125th. sec.).
(see Shutter speed)

Too low in contrast. The range in density in a negative or print is too small.
(see Contrast & Neg.)

Flat Lighting
Soft lighting that produces very little contrast on the subject plus a minimum of shadows.
(see Contrast & Soft Lighting)

General term for an artificial light source which provides a constant and continuous light. Usually a tungsten-filament lamp mounted in a reflector.
(see Blonde & Redhead)

Focal length
The distance between the film plane and the focal point (optical centre of the lens) when the lens is focused at infinity. The focal length of the lens is marked in millimetres on the lens mount. The principal focal point is the position of best focus for infinity. There are two principal focal points, if a lens is turned around a second focus is obtained. 'Reversed' lenses are often used in close-up Macrophotography because using a lens reversed allows a closer focusing distance.
(see Macro Lens & Macrophotography)

Focal plane
Plane on which a given subject is brought to a sharp focus, where the film is positioned.

Focal plane shutter
One of the two main types of shutter and used universally in 35mm SLR cameras, positioned behind the lens and in fact slightly in front of the focal plane; the shutter consists of either cloth or metal blades. When the camera is fired a slit travels across the image either vertically or horizontally. The width and speed of the slit determines the duration of the exposure.
(see Between-the-lens shutter & 35mm)

Focusing screen
Glass or plastic screen set at the camera's image-forming plane, where the image can be viewed and focused.
(see Finder)

Focusing Spot
A type of mains light that works like a High Powered slide projector. It can focus the flash or continuous light into a sharp beam of light, or project an image of 'light & shadow' onto the subject with special metal light pattern "slides" or "Gobos".
(see Gobos)

Focusing cloth
(see Darkcloth)

Density produced on a negative, print or trannie by chemical processing or accidental exposure to light, caused by
1. exposure to non image-forming light (possibly: opening the camera back in daylight),
2. too much handling in air during the development process,
3. over-developed,
4. outdated film or paper, or
5. storage of film or paper in a hot, humid place.
(see Outdated & Over printed)

The size of the negative, paper or camera taking area.
(see Large format, Medium format & 35mm)

Four Thirds system
A digital standard created by Olympus and Kodak. First introduced to the world in November 2003 with the Olympus E-1 camera. 4/3" or 4/3 describes the type of sensor and not the size of the light sensitive area. Olympus say the format name references the outer diameter of early vacuum image-sensing video camera tubes. 'Four Thirds' is the aspect ratio of the sensor 4:3 and its size is 17.3 x 13 mm.
(see Format & Micro Four Thirds system)

Front focusing
The tendency of a lens or sometimes the camera body to focus slightly in front of the subject. This may be eliminated by a camera menu adjustment, some DSLRs offer the ability to fine-tune the camera’s autofocus point for each lens used.
Cameras are designed and manufactured within certain tolerances. These variables include: reflex mirror alignment and the distances between the AF sensor to the focal plane, the secondary AF mirror assembly to the focus sensor, and the mounting flange to the film plane. Although it has always existed and effects both AF and manual focus cameras, it appears to be more of an issue today because the digital photographer can instantly enlarge the photo to 100%.
(see: Back focusing)

The name given by Nikon to its range of full frame format SLRs, the image sensor is virtually the same size as a 35mm film format. If a DX lens is mounted on a FX format digital SLR, the camera's 'DX-Crop Mode' automatically alters the image capture area accordingly.
(see DX)

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Gamma correction, gamma encoding or simply gamma, is the name of a nonlinear operation used to code and decode luminance, originally developed to compensate for the input/output characteristics of cathode ray tube (CRT) displays.

Large coloured sheets of a transparent medium which are used over any type of light to add colour. (Also the smaller C.C. & camera filters.)
(see CC filters)

Generator pack (Power pack)
The power pack used to link Large Studio flash lights to the mains.
(see Monobloc)

Giclée Print
The term 'Giclée' first appeared in fine art marketing at the end of the 80's. Giclée (pronounced "zhee-clay") is french for "squirt" or "spray." Produced by a large format ink jet printer on art-quality paper or canvas. The term, however, offers no standard for quality or print longevity.
(see Fine Art & Ink Jet Print)

Gigabyte (GB, Gig)
A measure of file size and storage capacity. Most consider a kilobyte to be 1,024 bytes, a megabyte to be 1,024 kilobytes, and a gigabyte to be 1,024 megabytes. However, some key standards groups assume a kilobyte to be 1,000 bytes, a megabyte to be 1,000 kilobytes, and a gigabyte to be 1,000 megabytes. Many data storage manufacturers use this latter measurement to define their device sizes, which leads to computers showing less storage capacity on a drive than the specificiations suggests.
(see Kilobyte & Megabyte)

A gobo (GOBO: 'GOes Before Optics' is a Film Industry term) is a template pattern device used to control the shape of emitted light. Made from either metal or glass which when added to a suitable light source can be projected onto "a photographic subject" e.g. a shuttered window effect onto a table. Usually the gobo is used inside a Focusing Spot Light, but an ordinary 35mm projector can be used on smaller scenes with simple card gobos!
(see Focusing Spot)

(See Contrast grade, Multigrade & Papergrade )

Grain sharp
Making a print 'grain sharp' means that it is printed in focus.
(see Grain)

The sand-like, granular appearance of a negative, print or trannie. Graininess becomes more noticeable with fast films and increased size of enlargement. (Granularity: The amount of grain clumping that has occurred within an emulsion. Also referred to as graininess.)
(see Emulsion, Enlargement & Fast film,)

Guide number
The number which indicates the effective power of a flash unit. For a given film speed, the guide number divided by the distance between the flash and the subject gives the appropriate f stop to use.

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Hammer head
A type of larger portable battery fed flashgun (normally a Metz)
(see Metz)

High Dynamic Range imaging, a technique to combine several exposures in order to achieve a similar vision to the human eye. Several bracketed photos are combined in a photo manipulation program. For example you can combine an interior shot and the view outside a window into one perfectly exposed HDR image.

High key
Term describing a photograph which contains large areas of light tones, with few mid-tones or shadows.
(see Low key)

High Resolution (High Res)
Refers to a relatively larger number of pixels per inch in a digital image or scan, which yields a large digital file.

The brightest areas of the subject or photograph.

Hold-back (shading)
Photo printing method to make parts of a picture lighter than it would normally have been.
(see Burning-in & Dodging)

A tube, usually made of metal or rubber, that prevents unwanted light from falling on the lens surface.
(see Flare)

Hot shoe
The electrical fitting on a camera that holds a small portable flash and links the gun to the camera shutter mechanism.. This direct flash-to-camera contact eliminates the need for a flash sync. cord.
(see Accessory Shoe, Flash sync. & Shutter)

An autofocus system that has trouble finding the focus in a low contrast image or in poor light 'hunts'; this is where the lens moves continuously from close-up to infinity looking for the correct point of focus .

Hyperfocal Distance
The Hyperfocal Distance or point is the nearest point to the camera which is regarded as acceptably sharp when the lens is focused at infinity. So when the lens is focused on the hyperfocal point, depth of field extends from infinity back to a distance halfway between the camera and the hyperfocal point. This method is used in fixed focus viewfinder and 'box' cameras to obtain a photo that would perhaps include both a far away mountain range and a close group of people in acceptable focus.
(see Depth of Field)

Popular name for a fixing agent, derived from an abbreviation of hyposulfite of soda, the misnomer applied to sodium thiosulphate during the 19th century.
(see Fix)

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Established in 1993 by eight industry vendors for the purpose of creating, promoting and encouraging the standardization and evolution of an open, vendor-neutral, cross-platform colour management system architecture and components. The outcome of this co-operation was the development of the ICC profile specification.
(see Colour Profile)

Image resolution
Digital photography: The number of pixels displayed per inch of printed length in an image, usually measured in dots per inch (dpi) or pixels per inch (ppi) The amount of detail in an image depends on its pixel dimensions, while the image resolution controls how much space the pixels are printed over. You can modify an image's resolution without changing the actual pixel data in the image all you change is the printed size of the image.
(see Pixel & File size)

Image Sensor
The Digital camera's image sensor is a device that converts an optical image into an electric signal. Either CCD or CMOS.
(see CCD & CMOS)

Image Size
The dimensions of a digital image, most clearly expressed in its pixel count, horizontally and vertically.
(see Pixel)

Incident light
Light falling on a surface (as opposed to reflected by it).
(see Meter)

Incident light reading
Measurement, of the amount of incident light falling upon a subject. The meter is placed close to the subject, pointing toward the light.
(see Meter)

Focusing point at which the lens gives a sharp image of very distant objects, such as the far horizon.

Infinity cove
(see Cove)

Ink Jet Print
An image on paper or other material such as a canvas produced by a process that sprays dyes or pigments through tiny nozzles onto the material.
(see Giclée Print)

(see diaphragm)

ISO (International Standards Organization)
The modern speed rating for photographic materials used instead of ASA or DIN*. The scale is identical to ASA (American Standards Association) where the rating is based on an arithmetical progression, using an average gradient system. Therefore ISO 200 film is twice as fast as ISO 100 film but only half as fast as ISO 400 film.
(see ASA & DIN)

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JPEG (Joint Photographic Experts Group) is a file compression method used in Digital Photography that shrinks a file's storage size, but which can also cause image degradation as a result of data loss.
(see Lossy)

Unit of energy in the SI (Système International) system of units. The joule is sometimes used in photography to indicate the output of an electronic flash.

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Unit of temperature in the SI (Système International) system of units. Kelvin is used to measure the colour temperature of light. Daylight films are designed for colour temperatures between 5200K and 5800K.

Converging verticals can make a building appear to be falling down (wider at the bottom than the top), this can be corrected by making sure the film plane is parallel to the photographed surface using either a Shift Lens or camera movements. It can also be corrected within Photoshop. Keystoning is also the term for the effect of a tilted (up or down) projector.
(see Camera movements, Converging angles, Movements, Photoshop, Rising front & Shift )

Kilobyte (KB, K)
A measure of file size and storage capacity referring to 1,000 or 1,024, 8-bit data units or characters.
(see Gigabyte)

Kodak trade name for Lith film.
(see Lith film)

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Large format
As the name implies this is the largest of modern film formats (the most popular being 5"x4" & 10"x8"), and they are especially suitable for high quality commercial work.
(see Medium format)

Well known reflector manufacturer who created the photographers folding 'spring out of the bag' style reflectors and Backgrounds.
(see Reflector)

Latent image
The invisible image left by the action of light on photographic film or paper. The light changes the photosensitive salts and when processed, this latent image will become a visible image.

The range of camera exposures from under to over exposure that will still produce an acceptable image from a specific film.
(See Exposure & Exposure latitude)

The beginning of a 35 mm or roll film, which is attached to the take-up spool.
(see Roll film & 35mm)

Lens shade
A Bellows or Hood at the front of a lens that keeps unwanted light from striking the lens and causing image flare. Should be sized to the particular lens to avoid vignetting.
(see Bellows, Flare, Hood & Vignetting)

Lens Speed
The largest lens opening, e.g. f2 not f16. A fast lens transmits more light and has a larger opening than a slow lens.
(see f-stop & Slow lens)

Light meter
(see: Exposure meter)

Light-field camera
Also called a Plenoptic camera. Uses a multi Microlens array to capture a scene. The need for initial focusing is eliminated as the chosen focus point and depth of field is calculated using 'Synthetic Aperture Photography' in post-capture computation. Go to http://raytrix.de for further explanation.
(see Lytro light-field camera, Microlens, Plenoptic illumination, Synthetic Aperture Photography)

Lith film
Very high-contrast B&W film which, after correct development with a special lith developer, gives negatives of black and white only (with no greys).
(see Contrast & Dev.)

Long lens
Term describing a lens in which the focal length is much greater than the diagonal of the film format (or standard lens) with which it is used. e.g. 300mm on 35mm format where the standard is just 50mm.
(see Focal length, Standard lens & Tele)

Many file formats use compression to reduce the file size of bitmap images (digital photo). Lossless techniques compress the file without removing image detail or colour information; lossy techniques remove detail. JPEG is the most common file format in digital photography but this is a "Lossy" file format. TIFF with LZW(Lemple-Zif-Welch) compression is the most popular lossless file format.
(see JPEG & TIFF)

Low key
Term describing a photograph in which the tones are mostly dark and there are few highlights.
(see High key)

Low Resolution (Low Res)
An image file that is one megabyte or less in size when opened in an image editing application. Useful for presentation purposes but insufficient for high quality printed reproduction except at small sizes.
(see Megabyte)

Measurement of "candle power" or light output, a unit of light falling on a surface.

(see Lumen)

Lytro Light Field Camera
A compact Plenoptic camera which uses existing photographic knowledge in a new way. An exciting prospect for the consumer market; although it is probably destined to become just a 'web tool' because of the technologically restricted image size of its output format. Go tohttps://www.lytro.com for more information.
(see Light-field camera, Plenoptic illumination, Compact camera)

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Macro lens
A lens that provides continuous focusing from infinity to extreme life-size 1:1 close-ups. Also used as a copy lens because of its highly corrected design and close-focusing. Macro lenses can also be used at ordinary subject distances
(see Copy, Close-up lens & Extension tubes)

Close-up photography in the range of magnification between life-size 1:1 and about ten times 10:1.

(see Film Back)

Mains flash
Not battery fed; large studio based Flash lights, run from mains electric.
(see Generator pack & Monobloc) .

To change a photograph either by a computer program, optical processes or by skilled hand.

Matrix Metering
Multi-segment metering (originally devised by Nikon for its FA SLR of 1983 under the name AMP: Automatic Multi-Pattern metering). Matrix was introduced to the world in 1988 with the Nikon F4, light coming from the subject passes through the lens into the viewfinder where it strikes the F4's 5 segment light meter, this offered the photographer a better chance of obtaining the correct exposure for the main component of a particular image. The latest Nikon flagship D4 has a RGB sensor with 91K (91,000) pixels. Produced by other manufactures under varying names.

Medium format
A larger format than the popular 35mm size, which can provide the image quality necessary for commercial reproduction, using 120, 220 or 70mm film. Various sizes can be shot, the most popular are 6cmx6cm, 6cmx4.5cm and 6cmx7cm.
(see 35mm)

Megabyte (MB)
A measure of file size and storage capacity referring to between 1,000,000 and 1,048,576, 8-bit data units or characters.
(see Gigabyte)

The manufacturers way of describing the resolution of a Digital camera; a 12 megapixel camera has a resolution of 12 million pixels. The 'image size' of a Nikon D600 24.3 megapixel camera is 6,016 x 4,016 pixels.
(see Pixel)

Memory Stick
A Sony memory card. Like Compact Flash and Smart Media it is a flash memory based storage system for use in digital cameras.
(see Compact Flash and Smart Media)

Data embedded and stored within a digital image file. It provides information concerning copyright, credit, restrictions, captions, photographer, keywords, or other characteristics. There are several forms of image metadata including EXIF which is used by digital camera makers and provides large amounts of photo information including the make & model, date & time, aperture and shutter-speed.
(see EXIF data)

An instrument with a light-sensitive cell that measures the light reflected from or falling onto a subject. Some types can also measure Flash light.
(see: Exposure meter & Incident light)

Well known German manufacturer of large portable battery flashguns.

Micro Drives
Very small1-inch Hard Drives (HD) designed to fit a CompactFlash (CF) slot. Today flash memory cards are available in much larger sizes.
(see Compact Flash)

Micro Four Thirds system (MFT)
A new standard created by Olympus and Panasonic for mirrorless interchangeable lens digital cameras. MFT has the same image sensor size and specification as the Four Thirds system but with smaller lenses and bodies because of its mirrorless design. A useful feature is that virtually any lens (e.g.: Leica) can be used on a MFT camera body using an adapter.
(see Four Thirds system)

Micro lens
The Micro-Nikkor is the Nikon Corporation's name for their close-up 'Macro' lens.
(see Macro lens)

A microlens is a small lens, generally with a diameter less than a millimetre (mm) and often smaller than 10 micrometres (µm). Microlens arrays are often used to increase the light collection efficiency of CCD & CMOS sensors.
(see CCD & CMOS)

(see Photomicrography)

Mirror (Mirror lens)
A long lens that uses mirrors within its construction. This allows an extremely long focal length lens to fit within a relatively short barrel. Also known as reflex or catadioptric (cat).
(see Long lens)

Model Release
A document signed by the subject (if under age, the subject's guardian) to permit the use of their likeness in advertising or commercial photography.

Modeling light
A high powered bulb in a Mains Flash unit which is used to help the photographer judge what effect the flash light will have on the subject. It also describes a light used to enhance a three-dimensional effect.
(see Mains flash)

Type of mains flash that is smaller than the Generator style items. They are self contained and can be used more easily on location.
(see Generator pack)

Monorail camera
Large format camera, constructed on a single rail. Offers the maximum of camera movements.
(see Baseboard, Camera movements, Field camera & Technical)

Large format camera movements to help focus, shape, composition or converging angles (swing, shift & tilt) .
(see Camera movements& Converging angles)

Abbreviation for Megapixel.
(see Megapixel)

Modern lenses are made up of many individual glass elements, these elements improve the overall image quality compared with a simple 'single' or 'double' element lens, however, extra elements can reduce the performance by absorbing incoming light. A transparent lens 'Coating' (single or multi) aids the passage of light, reduces 'flare' and also improves contrast.
(see Flare)

(see Bracketing)

Photographic B&W paper that provides all the different grades of contrast from one box. Invented by Ilford in the 1950's, but versions are now manufactured by all the major makers.
(see Contrast grade paper)

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Neg. (Negative)
Developed film that contains a reversed image of the original scene (in a colour negative the colours are also reversed, and appear as their complementaries.). Light shone through the transparent negative will make a positive (normal) print on photographic paper.

Neg. carrier
Negative holder used in an enlarger. It may be adjustable for different formats and is designed to exclude unwanted light from the edges of the neg .
(see Format)

Neutral density filter
A neutral grey camera filter which is used to reduce the amount of light entering the camera when a slow shutter speed or wide aperture is needed.
(see Aperture & Shutter speed)

Noise Reduction
A major picture quality difference between a digital compact and a DSLR is that the compact produces photos with more noise, similar to the 'grain' of a high ISO traditional film. When a high ISO is set the camera has to amplify the signal received from the sensor and this increases background electrical noise. The larger image sensor of the DSLR has bigger photosites therefore more light gathering capacity and a larger signal to noise ratio.
To overcome this problem manufacturers have incorporated noise reduction systems into their cameras. These do reduce noise but also introduce a smoothing effect. Creating a 'smearing' mostly revealed in grass, brickwork and any subject with a fine, repetitive pattern.
(see ISO & DSLR)

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One shot back
Digital camera back for Large or Medium format cameras that can shoot a scene in one pass like ordinary film (not three like the RGB Scanning backs) can therefore be used with live subjects, not just still life. (see Large format& Scanning back)

Open flash
Method of using numerous flash firings to build-up 'flash power'. During which time the shutter is kept open, this method can only be used when the shutter speed is unimportant because of poor existing lighting.
(see: Existing light, Flash range & Shutter speed)

Term used to describe 'Black & White' emulsions that are not sensitive to red light, B&W printing papers are usually orthochromatic.
(see Panchromatic)

Film outside of the expiry date stamp, found on the film box. (this date indicates the useful life of the material in terms of maintaining its published speed and contrast.)
(see Contrast & Speed)

Over exposed
A situation in which too much light reaches the film or sensor and produces a dense negative or a very light positive image.

Over printed (or Overdevelopment)
Term indicating that the amount of recommended development has been exceeded. It can be caused by prolonged development time or an increase in temperature, and usually results in an increase in density and contrast.
(see Contrast)

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Packshot Photography
Usually called "Pack Shot". A product photo used for marketing purposes. The packshot's main purpose is to accurately reflect the product as it appears in real life. Correct colour, shape and form with logos and lettering in view.

Term used to describe 'Black & White' emulsions that are sensitive to all visible colours. Most modern films are panchromatic.
(see Orthochromatic)


Technique for photographing a moving subject. While the shutter is open, the photographer swings the camera following the moving subject. This creates a blurred background, but a sharp subject. The technique works best with slower shutter speeds.
(see Shutter speed)

Panoramic camera
Camera with a special type of scanning lens which rotates. Or a static lens camera with a wide format e.g. 6cm x 17cm.

Paper grade
Numerical and terminological description of paper contrast:
numbers 0 -1 soft; number 2 normal; number 3 hard; numbers 4 very hard.
(see Contrast grade paper & Multigrade)

Parallax error
The difference between the image seen by the viewing system and that recorded on the film. Problems occur as the subject moves closer to the taking lens when using TLR cameras. Only through-the-lens viewing systems can avoid parallax error.
(see TLR)

Optical device, found on SLR cameras, which corrects the image (reversed by the lens), allowing eye-level viewing and focusing via the viewfinder.
(see Finder, Focusing screen, & SLR )

Perspective control lens
(see Shift)

Bright tungsten filament bulb used as an artificial light source. The bulb is over-run and so has a short life.
(see Tungsten light)

The art, science and practice of creating durable images by recording light, either electronically or chemically. Normally a lens is used to focus the light reflected from an object to form an image inside a camera during a timed exposure. In a Digital camera, an electrical charge at each pixel is processed and stored as a digital image file. In traditional film emulsions an invisible latent image is formed, which is then chemically developed into a visible image.
The word photography is based on the Greek words photos meaning 'light' and graphé meaning 'drawing', together meaning drawing with light.

Sometimes called Microphotography. The technique of taking extreme close-up photos through the lens of a microscope, it is used to achieve magnifications greater than those obtainable using a Macro lens.
(see Macro lens & Macrophotography)

Best known and well used Image manipulation computer program (by Adobe Systems); which has gradually entered the photographers vocabulary with words like: 'Photoshoped' meaning retouched or manipulated. Photoshop 1.0 was released in 1990 for the Macintosh.
(see Retouching)

Pincushion effect
Lens aberration (distortion) causing parallel, straight lines at the edge of the image to curve inwards.
(see Aberration, Distortion & Barrel distortion)

Pinhole Camera
A camera without a lens, just a light tight box with a small hole at one end.
(see Camera obscura)

A single picture element of a digital photo. Digital Bitmap images (raster images) use a grid of colours known as pixels to represent images. Each pixel is assigned a specific location and colour value.The whole image would contain millions of individual pixels.
(see Image resolution & File size)

Plenoptic illumination
An idealized function used in computer science to express the image of a scene from all possible viewing positions, viewing angles and time.
(see light-field camera)

A software module that can be used by Photoshop (and other image editing applications) to provide additional functions including: import of RAW camera files, file format conversions and creative image filters.
(see Photoshop & RAW)

Point and Shoot
A point and shoot camera (or compact camera), is a camera designed for a quick and simple operation. Using either an autofocus or a focus free lens, an automatic exposure system and a built-in flash; you point the camera and simply press the shutter button, and the camera does the exposure and focus calculations for you. Popular with people who want a camera that is both easy to use and also small enough to carry in a jacket pocket or hand bag.

Polaroid back
A pre-digital proofing system. A special camera back loaded with instant film, mostly used with either medium or large formats, it was used by photographers to check the lighting, composition and basic exposure before shooting with traditional film.
(see Film back)

(see Multigrade)

Post Production
Everything after the photo shoot. Post production includes editing, colour correction, cropping, etc.
(see Colour correction and Cropping)

(See Burning-in)

Glass block which bends light to varying degrees, depending on wavelength, so separating it into its component colours. Also sometimes the given name to pentaprism finder.
(see Pentaprism & Finder)

Process paid
A pre-digital terminology: Colour Reversal Film processing by the manufacturers own 'Processing Lab' included in the purchase cost. Today this is not offered by any major film manufacturer.
(see Reversal Film)

The sequence of steps in which the latent photographic image is converted into a visible, permanent image.
(see Dev. & Latent image)

Pulled (Pulling)
Decreasing the development time of a film to slow its effective speed, e.g.50 ISO instead of its recommended 100 ISO.
(See Uprating & ISO)

Pushed (Pushing)
Increasing the development time of a film to increase its effective speed, e.g. 200 ISO instead of its recommended 100 ISO.
(See Uprating & ISO)

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A device included on many direct vision cameras as an aid in focusing. The photographer assesses subject distance, usually by comparing two overlapping images in the viewfinder. This device may be linked directly to the lens focus control, to give a coupled rangefinder
(see Coupled rangefinder)

An unprocessed digital file direct from the camera. Not a 'standard' file format like TIFF or JPEG. Usually the camera manufactures software or 'plug-in' must be used to open a RAW image file.
The results of working on a raw image and altering the exposure, white balance, brightness or contrast would show fewer visible artifacts compared to a corrected 'straight from camera' jpeg.
Using the raw image file gives the photographer more scope for both corrections and manipulations without adding additional flaws.
RAW is usually used only when additional computer processing is intended or post-production time allows.
(see JPEG, TIFF & Plug-in)

RC paper
Modern Resin Coated (plastic) photo paper which does not need as long washing than the traditional fibre paper (see Fibre (FB) & Resin coated paper)

Most films are designed to be exposed within a certain range of exposure times. When an exposure time falls outside of this range a film's characteristics may change. Loss of effective film speed, contrast changes, and colour shifts are the common results. This is called reciprocity effect.
(see Colour Balance, Contrast & Exposure)

Recycling time
Time taken by flash unit to recharge, between firings.

A Type of Tungsten lighting from various manufactures (rated at 800w).
(see Blonde & Tungsten light )

Any surface from which light can be reflected. Used to reflect light from a main source into the shadow areas.
(see Lastolite)

Reflex lens
(See Mirror lens)

To change the resolution of an image through interpolation. Resampling downwards discards information and resampling upwards creates new information based on adjacent pixels.
(see Image resolution)

Resin-coated paper (RC)
Printing paper with a water-repellent base. RC papers can be processed faster; requires less washing, and dry far more quickly than fibre-based papers.
(see Fibre (FB) & Multigrade)

(see Image resolution )

Fine, irregular pattern appearing on the surface of an emulsion which has been subjected to a sudden and severe temperature change during development.

After-treatment carried out on negatives, trannies, prints or Digital files to remove blemishes or change tonal values. Now, carried out by 'Photoshop' rather than by hand.
(see Photoshop)

Reversal film
Film or paper designed to produce a positive directly from exposure and processing, without the need of a negative.
(see Exposure & Trannie)

The way that the colours are recorded in Digital imaging. A large percentage of the visible spectrum can be represented by mixing Red, Green and Blue coloured light in various proportions and intensities.
(see CMYK)

Ring Flash
Type of flash unit which fits around the lens to produce flat and shadow less lighting.

Rising front
A camera movement enabling the photographer to raise or lower the front lens panel from its central position (on most Large format cameras). Its main use is to maintain correct verticals in architectural photography.
(see Converging angles, Large format, Movements & Shift)

Roll film
120 format film which has an paper backing and is supplied wound on an open spool (rather than in a light-tight cassette). Also the less common double length 220. All these films are used in Medium Format cameras. The term should be applied to all camera films in roll form, including 35 mm.
(see: Cut film, Medium format & 35mm)

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Secure Digital
Secure Digital (SD). A small memory card which uses flash memory as a base for storing digital photos.
(see Compact Flash)


Darkroom lighting, allowing safe handling of light sensitive materials (e.g. deep red for B&W paper).

A characteristic of the observation of colour. Saturated colours are called vivid, strong, or deep. Desaturated colours are called dull, weak, or washed out.

Scanning back
High quality digital camera back for Medium or large format cameras which scans in three passes (RGB) one pass for each colour, therefore only used with still life studio subjects.
(see One shot back)

(see Focusing screen)

Screw mount lens
Lenses with screw mounts are probably still available but these are generally only needed for older cameras, the last popular 35mm SLRs fitted with a screw mount were the Pentax of the late sixties and the Praktica of the early seventies.
(see Bayonet & SLR)

Lighting attachment which when placed in front of the lamp reduces its light intensity.

A post production process that increases contrast and adds apparent clarity or sharpness to a digital image. The most common method is called unsharp masking (USM).
(see Post Production & Contrast)

Sheet film
(See Cut film)

Movement on large format camera (or special "shift lens" in other formats) which can eliminate converging angles.
(see Converging angles, Movements & Rising front)

Blades or a curtain that controls the time during which light reaches the film.
(see Focal plane shutter & Between-the-lens Shutter)

Shutter speed
The time in which the shutter stays open to light, measured in fractions of seconds, (1/8000th a second is a very fast shutter speed and 1/2 second is very slow).

Silver Halide
Chemical compound of silver with a halogen. Silver bromide is the principal light sensitive constituent of modern photographic emulsions.
(see Emulsion)

A photo-electric cell which fires additional flash units simultaneously when it is activated by the light from another flash source set by the camera.

A photographic trannie (positive) mounted for projection (usually 35mm).
(See Trannie & 35mm)

Slow film
Film which has a limited sensitivity. Such films have low ISO speeds (e.g. 25 or 50 ISO).
(see Fast film, Film speed & ISO)

Slow lens
A lens with a small maximum aperture. (i.e. f8)
(see Aperture & Fast lens)

(Single Lens Reflex) A Camera in which the photographer views the scene through the same lens that takes the picture thanks to a system of mirrors and prisms.
(see Prism & TLR)

Single Lens Translucent, is Sony terminology. In a SLT a translucent mirror replaces the usual SLR moving mirror, this splits the light rays from the lens into about two-thirds hitting the CCD, while the rest is reflected onto the autofocus sensor. This allows ultra-fast shooting and accurate auto focus tracking. It has several disadvantages, including that around a third of the light is lost to the AF sensor and that the photographer has to use an 'electronic viewfinder'. The Translucent Mirror is not new, Canon had tried this fast solution in the 60's and 80's with the Canon Pellix and Canon EOS RT.
(see EVIL & CCD)

Smart Media
A wafer-thin sized memory card which uses flash memory as a base for storing digital photos.
(see Compact Flash)

Cone-shaped shield used on lights to direct a small patch of light over the subject.

Soft box
A 'framed' diffuser that fits over the Light and creates a more natural soft light.
(see Diffuser)

Soft Lighting
Lighting that is low in contrast, such as on an overcast day.
(see Contrast & Diffuser)

Sensitivity of a photographic emulsion to light. Films are given ISO numbers which denotes its speed. The term is also used to denote the maximum aperture of a lens.
(see Fast film, Fast lens, Film speed, Slow film, Slow lens & ISO)

Spill kill
An attachment on a Mains Flash unit (when using a brolly) that stops the spill of light to the sides and possibly indirectly onto the subject.
(see Brollies & Mains flash)

Spot meter
Narrow-angle exposure meter used to take accurate reflected light readings from a small area of a subject; can also be useful when the photographer is some distance away from the subject.
(see Exposure meter)

The Standards (front & back) of a large format camera where you perform the "movements". These movements allow the photographer to manipulate the photograph.
(see Monorail, Movements & Technical)

Standard lens
A lens that makes the image in a photo appear in perspective similar to the original scene. It has a focal length approximately equal to the diagonal of the film format with which it is used (e.g. 50mm with 35mm cameras). Also known as a normal lens.
(see Format, Tele, Wide & Zoom)

Stop down
Changing the lens aperture to a smaller opening; for example, from f4 to f5.6. This increases depth of field.
(see Aperture, Depth of field, f-stop & Wide open)

(see Aperture & f-stop)

An acid rinse, usually a solution of acetic acid, whose purpose is to stop development by neutralizing unwanted developer when processing black-and-white film or paper.
(see Dev.)

Generic term for electronic flash.

Stroboscopic Flash
Stroboscopic or Repeating Flash is a 'mode' available on some flashguns where under certain lighting conditions it can produce multiple exposures in a single frame. A good use of this feature would be 'the swing of a golfer' or the movement of a bouncing ping pong ball .

Swimming Pool
There are various unusual names given to large photographic lights, including 'Fishfryers' & 'Eggcrates', a swimming pool is usually a large overhead light often used in automotive photography and is suspended from the studio ceiling or attached to a large boom stand.

Swing, the movable front(lens) and back (film) panels (standards) of most view and monorail cameras. This allows the photographer to manipulate the perspective and depth of field.
(see Depth of field, Monorail, Movements, & Standard)

Synchronized flash
(see Flash sync.)

Syncro Sun
A term used to describe a combination of sunlight and flash light, where flash is used as a fill-in. The camera is set to synchronize the flash at shutter speed which would also allow the sunlight to register and not overexpose, usually using the fastest shutter speed available (e.g. 1/250th).
(see Flash sync., Balanced Fill Flash)

Synthetic Aperture Photography
SAP or “digital refocusing”. By taking an appropriate number of samples using the microlens array in a Light-field camera, a computer can devise the probable view that would be captured by a traditional camera with a large aperture. This essentially allows the photographer to refocus a snapshot after it has been captured, It works best in macrophotography, where the scene is close to the camera.
(see Aperture, Macrophotography, Microlens, Light-field camera)

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T Setting
A 'Time' setting mark found on some shutter controls. This setting is used for shutter speeds that are longer than the specified timed settings. The first press on the shutter leaves the shutter open, and it stays open until the photographer presses the shutter for a second time.
(see Shutter)

Container for holding chemical solutions for processing films. Some tanks are for darkroom use only; others must be loaded in the dark, but can be used in daylight.
(see Daylight Tanks)

Technical camera
Not unlike a Field Camera but is made of metal (Large or Medium format with movements on front and rear standards, but less than a Monorail!). Used in the field and the Studio, a good all rounder.
(see Field camera, Large format, Monorail, Movements & Standard)

Tele (telephoto)
A telephoto lens has a longer focal length and narrower field of view than a normal lens and enlarges distant subjects. Depth of field decreases as focal length increases. (Telephoto lens construction: this allows a long focal length with short back focus, making for relative compactness).
(see Depth of field, Long lens , Standard lens & Wide)

Test strip
Method of calculating exposure in photographic printing. A range of exposures are given to a strip of paper, from part of the image, this helps judge the correct exposure for the final print.
(see Exposure)

A negative that is underexposed or underdeveloped and therefore appears less dense than a normal negative. A thin neg will need a harder paper to print correctly.
(see Contrast, & Papergrade )

The most popular film size; 35mm wide with punched sprocket holes and made for both still and motion picture cameras. In 1913, Oscar Barnack, of 'Leitz ' first used it in a still camera when he created the 'Leica' prototype using movie film stock. The format is 24 x 36mm, unchanged from Barnack's prototype. In relation to other formats, 35mm gives the best compromise between image quality and versatility. Nowadays also the size of the sensor on a full frame DSLR camera.
(see Format, DSLR)

TIFF (Tagged Image File Format) is a common file format used in Digital Photography. This high quality file (which is lossless compared with a JPEG) can also contain colour management profiles and be colour separated.
(see JPEG & Lossy)

A Large Format camera movement. The photographer tilts the lens or film standard to increase or decrease the depth of field.
(see Depth of field, Movements & Standard)

Twin Lens Reflex camera. A fixed mirror replaces the SLR's flip-up mirror, so making this design very quiet. (Medium Format) 6cmx6cm. Rollei is the best known. Parallax error can cause the photographer problems at closer distances.
(see Medium format, Parallax error & SLR )

Cold tones (bluish) and warm tones (reddish) refer to the colour of the image in both black-and-white and colour photographs.
(see Colour Cast)

Solutions called toners are used to change the colour of a black and white photographic image. Various toners are available which add there own Cold or Warm tones to the print (Sepia is the most well known).
(see Tone)

A positive photographic image on film, usually colour but can be B&W, viewed or projected by light shining through the film.

(see Trannie)

Through The Lens: A metering system in which a light meter within the camera body measures exposure from the image-forming light that has passed through the lens.
(see Meter)

(see Extension tubes)

Tungsten film
Colour film balanced for non-daylight sources (usually studio-type tungsten lamps) of 3200 or 3400K.
(see Colour balance)

Tungsten light
Artificial light from either tungsten filament or tungsten halogen lamps.
(see Blonde, Redhead & Tungsten film)

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A Band of wavelengths within the electromagnetic spectrum invisible to the human eye which are shorter than the blue end of the spectrum. All films are sensitive to some ultraviolet radiation. It shows as increased haze, particularly in distant views and at high altitudes, and may give a blue cast to a photograph.

Under exposed
A condition in which too little light reaches the film or sensor, producing a thin negative, a dark positive image or a muddy-looking print.
(see Contrast, Neg, Over exposed, Thin & Paper grade)

Under printed & Under development
A reduction in development which is usually caused by a shortened development time or a decrease in the temperature. It results in a loss of density and a reduction in contrast.
(see Contrast & Dev.)

Uprating (up rated)
A technique where the suggested film speed is deliberately exceeded. The photographer sets a higher film speed on the camera, so causing underexposure, which then is balanced by overdevelopment. Also known as "pushing". The opposite, shooting at an ISO rating below that suggested, and underdeveloping, is known as "pulling".
(see Pulled , Pushed & ISO)

USM (Ultra Sonic Motor) is a Canon devised Autofocus SLR lens motor system. USM lenses are usually quicker to focus, more compact, with greater operational simplicity and virtually silent compared to their earlier 'Arc Form Drive'(AFD) cousins. USM lenses only work with the Canon 'EOS' camera system, introduced in 1987.
(see SLR & EOS)

UV filter
Filter which may be used to absorb UV radiation, to reduce its effect.
(see Ultraviolet)

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Variable contrast paper
(see Multigrade paper)

View camera
Large format camera, which has a ground glass screen at the image plane for viewing and focusing.
(see Baseboard, Field camera, Large format, Focusing screen, Monorail & Technical)

(See Finder)

Fall-off in illumination at the edges of an image. This can be caused by poor lens design, using a hood not matched to the lens, or using too many filters at the same time.

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A Short focal length lens which takes in a greater angle of view than a standard lens. Depth of field increases as focal length decreases.
(see Focal length, Tele & Standard lens)

Wide-angle lens
(see Wide)

Wide open
Setting the lens aperture to its largest possible opening; for example 24-70mm f2.8 zoom opens to a maximum of f2.8. 'Wide open' creates a shallow depth of field.
(see Aperture, Depth of field, f-stop & Stop down)

White Balance
Depending on the lighting conditions, a pure white in a photograph may appear slightly yellow or blue. The white balance control settings on a "Digital Camera" will help to eliminate unwanted colour bias by actually controlling the camera's colour temperature response. C.C. filters or a specially balanced film must be used when a film camera is utilized under the same lighting conditions!
(see Colour Balance)

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XD Picture Card
A very small memory card which uses flash memory as a base for storing digital photos.
(see Compact Flash)

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Zone system
A system of 'relating exposure readings to tonal values' in picture-taking, development and printing, popularized by the American photographer Ansel Adams.

A Lens which is constructed to allow a continuously variable focal length; in effect, this gives you many lenses of different focal lengths in one unit. (e.g. 80-200 mm).
(see Focal length, Standard lens, Tele & Wide)

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