Copy of `Digital Exposure - filming glossary`

The wordlist doesn't exist anymore, or, the website doesn't exist anymore. On this page you can find a copy of the original information. The information may have been taken offline because it is outdated.

Digital Exposure - filming glossary Category: Film and Animation > Photographic and Digital Imaging terms Date & country: 15/08/2008, CA Words: 796

Gray level
A shade of gray assigned to a pixel. The shades are usually positive integer values taken from the gray-scale. In a 8-bit image a gray level can have a value from 0 to 255

Gray scale
An image type that contains more than just black and white, and includes actual shades of gray. In a grayscale image, each pixel has more bits of information encoded in it, allowing more shades to be recorded and shown. 4 bits are needed to reproduce up to 16 levels of gray, and 8 bits can reproduce a photo-realistic 256 shades of gray

Grayscale image
An image consisting of up to 256 levels of gray, with 8 bits of colour data per pixel

GRC
An acronym for Grey Component Replacement, a technique for reducing the amount of cyan, magenta and yellow in the mid tone areas and replacing them with the appropriate level of black

Ground glass
Frosted glass used as a viewing mechanism in cameras without prisms. The glass is placed so that the lens projects the image against the glass for focusing and composition purposes

GUI
Pronounced 'Gooey', stands for graphic user interface. Refers to the computer interface with software in a user friendly appearance

H&D curve
Another name for the D/log E curve, after its originators, Ferdinand Hurter and Vero C. Driffield

Halation
Is a diffused ring of light typically formed around small brilliant highlight areas in the subject. It is caused by light passing straight through the emulsion and being reflected back by the film base on the light sensitive layer. This records slightly out of register with the original image

Halftone image
An image reproduced through a special screen made up of dots of various sizes to simulate shade of gray in a photograph. Typically used for newspaper or magazine reproduction of images

Halftone screen
A pattern of dots of different sizes used to simulate a continuous tone photograph, either in colour or black and white

Halo
A light line around object edges in a image, produced by the USM (sharpening) technique

Hanger
A frame for holding sheet film during processing in a tank

Hard copy
Refers to a print or proof, as opposes to viewing on a monitor

Hard drive
A built-in or off-line fixed storage medium which holds large amounts of data that can be accessed rapidly depending on the power of the computer

Hard proof
A printed proof of an image or document, intended to accurately convey colour. Contrast with soft proof

Hardeners
Are chemicals often used with a fixing bath to strengthen the physical characteristics of an emulsion. The most common hardeners are potassium or chrome alum

Header
Technical information packaged with an image file, which may be of use in displaying the image (e.g., length and width in pixels), identifying the image (e.g., name or source), or identifying the owner

High contrast
A wide range of density in a print or negative

High key
A light image that is intentionally lacking in shadow detail

High-bit
An RGB system or image containing more than 24 bits of colour data per pixel

Highlights
The whitest or brightest part of an image; the opposite of shadows

Histogram
A graphic representation of how brightness and darkness pixels are distributed in an image. A histogram skewed heavily to the left indicates a dark image, while a histogram skewed to the right indicates a light image

History palette
The history palette lists the actions that have been done to an image and allows you to step forward or backward to a certain point

Honeycomb
Grid which makes light from a flash (or other source) more directional, like a spot rather than a flood

Horizontal Resolution
The number of vertical lines that a system is capable of producing (counted on a horizontal axis)

Host
The computer that performs centralized functions in a network

Hot Shoe
A flash connector generally found on the top of the camera that lets you attach a flash unit and trigger it in sync with the shutter

HSL
Hue, Saturation, and Lightness. A method of describing any colour as a triplet of real values. The hue represents the colour or wavelength of the colour. It is sometimes called tone and is what most people think of as colour. The hue is taken from the standard colour wheel and is thus calibrated in degrees about the wheel. Saturation is...

HTML
Hypertext Markup Language. An encoding format for identifying and linking electronic documents used to deliver information on the World Wide Web

Hue
The aspect of colour that distinguished it from another colour (what makes a colour red, green, or blue). Hue is distinct from saturation, which measures the intensity of the hue

Hue error
The degree of contamination in a process colour ink or other pigments that alters its appearance from that of a perfect process colour. For example most magenta inks are contaminated with yellow, making them appear to be red, rather than purplish-red

Hybrid Imaging
Electronic imaging systems that mix traditional silver-halide technologies with digital imaging technologies

Hydroquinone
A developing agent, also know as Quinol

Hyperfocal distance
The distance to the nearest plane of depth of field ( the nearest object in focus) when the lens is focused on infinity. Also the distance to the plane of sharpest focus when infinity is at the farthest plane of the depth of field. Focusing on the hyperfocal distance extends the depth of field from half the hyperfocal distance to infini...

Hyperlinks
Typically text, but also graphics, that serve as links that let you move around on the Internet and connect to different web sites. Hyperlinks are usually blue and underlined

Hypo
A common name for any fixer; from the abbreviation for sodium hyposulfite, the previous name for sodium thiosulfate (the active ingredient in most fixers)

I/O
Acronym for input / output. Input may be a camera, tape, disk, video, scanner, and output may be tape, disk, CD-ROM, film recorder, printer

ICC
The International Colour Consortium, An industry group that has endorsed a standard format for device profile

Icon
This is a little picture on a computer screen that represents the various functions of the computer. Generally the user clicks on an icon to start an application or function

Ilfochrome
Formerly Cibachrome. A type of colour printing that produces positive prints directly from transparencies

Illuminance
Is the term quantifying the illumination of, or incident light falling on a surface

Image Capture
The use of a device, such as a scanner or digital camera, to create a digital representation of an image. This digital representation can then be stored and manipulated on a computer

Image editor
Software programs that have been designed specifically for capturing, creating, editing, and manipulating images. Examples of these programs are Adobe Photoshop, Adobe Illustrator, Macromedia FreeHand, and CorelDRAW

Image file size
The amount of computer storage space a file requires; usually measured in kilobytes (K) or megabytes (M, MB, mgs or 'megs'). An image file that is 5 x 7 inches, 8-bit gray (as in a black and white photo), resolution 300dpi, is 3M in size. (A floppy disk holds 1.3M)

Image format
Refers to the specification under which an image has been saved to disk or in which it resides in the computer memory. There are many commonly used digital image formats in use. Some of the most used are TIFF, BMP, GIF,and JPEG. The image format specification dictates what image information is present and how it is organized in memory. ...

Image plane
Is the plane commonly at right angles to the optical axis at which a sharp image of the subject is formed. The nearer the subject is to the camera, the greater the lens image plane distance

Image processing
The general term 'image processing' refers to a computer discipline wherein digital images are the main data object. This type of processing can be broken down into several sub-categories, including: compression, image enhancement, image filtering, image distortion, image display and colouring

Image resolution
The amount of data stored in a image file, measured in pixels per inch (dpi)

Image size
Describes the actual physical dimensions of an image, not the size it appears on a given display device

Image Support
Hardware (scanner, workstation, printer) and software support for image as a system-recognized information type. Typically, although not necessarily, support for optical storage devices is included

Imagesetter
A device that uses laser light to expose film at high dpi resolution, usually 1200 dpi or higher. Most imagesetters have a maximum dpi of 4000. When generating screens or dots for halftones, each dot is created from the smaller dots that are determined by the dpi resolution. Imagesetters come in many different sizes and formats. They ca...

Import
To access a separate file while working on a document within an application for use in that current document

Incandescent lamp
An electrical lamp in which the filament radiates visible light when heated in a vacuum by an electrical current

Incident light
The light actually falling on a subject, which may not be the same as the amount of light being reflected by the subject

Incident meter
A hand-held Exposure meter that measures the intensity of light falling on the subject. To use it, you usually aim the hemispheric dome toward the camera. Most incident meter can also be used in a mode to measure reflected light

Index of refraction
A property of a medium that measures the degree that light bends when passing between it and a vacuum

Indexed colour image
An image where each pixel value is used as an index to a palette for interpretation before it can be displayed. Such image must, therefore, contain a palette which has been initialized specifically for a given image. The pixel values are usually 8-bit and the palette 24-bit (8-red, 8-green, and 8-blue)

Indoor film
Film formulated to give correct colour rendition when photographing subjects under 3200K light. It is also called 'tungsten' film. Most film is balance for daylight and if you use daylight film with household lamps or photographic lamps, the colours will be slightly reddish or orange. The light from an electronic flash is simi...

Infinity
In photographic terms is a distance great enough to be unaffected by finite vibration. In practice this relates to most subjects beyond 1000 meters or in landscape terms, the horizon. When the infinity distance is within the depth of field all objects at that distance or farther will be sharp

Infrared
The region of the electromagnetic spectrum adjacent to the visible spectrum, just beyond red with longer wavelengths

Ink jet
A non impact printing technology where ink droplets are propelled at the paper to form characters or graphics. Can be B&W or colour

Input
Any type of information that is fed into a computer. Input can come from digital cameras, scanners, keyboards or a number of other devices

Instrument metamerism
A phenomenon in a scanner in which two colours that appear the same to an observer are registered as different by the scanner, or two colours that look different to an observer are accepted as identical by the scanner. Instrument metamerism is a non-recoverable error, because the input cannot be determined from the output

Integration
Integration in photographic analysis is defined as the method of averaging all density ( illumination ) values either in R, G, and B, or as neutral density and saving this aggregate value to determine exposure in the camera or the darkroom

Intelligent Scanner:
Scanner with additional image processing capabilities, such as OCR, bar code reading, etc

Intensifier
Chemical treatment for adding density to an underexposed or underdeveloped negative or print. With prints, it is normally easier to re-make the print; with a negative, the loss of quality is normally so bad with all but the largest formats that the results are unacceptable

Intensity
The relative brightness of a portion of the image or illumination source

Interface
The process of making components or peripherals work together

Interlaced scanning
A scanning process in which all odd lines then even lines are alternately scanned. Adjacent lines belong to different fields

Internegative
A negative created directly from a colour-reversal (positive) or black-white positive film. It is the negative copy of the camera original

Interpolation: interpolate:
1. to insert between or among others 2. to change by putting in new material 3. to estimate a missing value by taking an average of known values at neighboring points

Interpositive
A positive transparency image generated as an intermediate step to enlarge an image in positive form either from a negative or positive material

Inverse square law
A law of physics that states that light from a point source fall off inversely to the square of the distance. As a example, if a light is 10 feet from your subject and you move it to 20 feet, you'll only have 1/4 the lighting intensity. If you move the light to 40 feet, it will now have only 1/16th the intensity

ISA
a 16-bit bus for PCs

ISO
Although the letters actually stand for International Standards Organization, they also indicate a film's sensitivity to light, or as more commonly referred to, its speed. The term pronounced by the individual letters: I--S--O, not as if it were the word 'ayso' The early term was ASA, which stood for American Standards Organiz...

ISO-9660
A file system format standard developed for CD-ROMs using the CD-XA encoding standard. It is supported by Microsoft operating systems, UNIX, and Macintosh

IT8


Jaggies
Stair-like lines that appear where there should be smooth straight lines or curves. Jaggies can occur for a variety of reasons, the most common being that the output device (display monitor or printer) does not have enough resolution to portray a smooth line. In addition, jaggies often occur when a bit-mapped image is converted to a dif...

Java
A programming language developed by SUN. Among other features, it allows the programming of interactive software for the Internet

Javascript
A scripting language, developed by Netscape® Communications. Javascript is the language that allows the images on the top of this page to hi-light as you roll your cursor over them. Javascript code can be placed directly onto web pages

JPEG
JointPhotographicExperts Group (the committee that established the baseline algorithms), .jpg. . A JPEG is a graphic image file created by choosing from a range of compression qualities (actually, from one of a suite of compression algorithms). When you create a JPEG or convert an image from another format to a JPEG, you are asked to...

JPEG compression
A standard developed by JPEG for reduction in the amount of data required to represent an image and therefore the hard disk space needed to store it. The techniques involved in compression may result in loss of actual data, which may result in irregular rasterization of an image or granularity. JPEG compression is defined only for still...

JPEG2000
The new JPEG compression standard that will be used in digital cameras and software starting in 2001. It will feature higher compression but will less image quality loss

Jukebox
A storage device for multiple optical disc, and one or more discs drives. It will automatically select or changeover as needed. Also Kodak's term for Photo CD's automated disc library

Juxtapose
In composition, to place two objects close together or side by side for comparison or contrast. Often helpful in showing scale in an image

K (Kelvin)
Abbreviation for Kelvin temperature, the measurement of the redness or blueness of white light. This is written without the degree sign. Daylight at noon, for example, has a Kelvin temperature of about 5500K, while photographic tungsten lamps are 3200K. Technically it is a measurement of the colour of white or gray based on the temperat...

K 14
Kodak's chemical process for developing Kodachrome slides

KB
Can be used to mean either a keyboard for a computer or more commonly 'KB' means a kilobyte of data

Kernel size
The number of pixels sampled as a unit during image manipulation and sharpening processes

Kerning
Tightening the space between letters

Key light
A studio light used to control the tonal level of the main area of the subject

Keystoning
The distortion of a projected slide or movie caused by the projector lens axis not being at a 90 degree angle to the screen. The image will appear wider at one edge than on the opposite and the image will not be uniformly sharp

Kilobyte
An amount of computer memory, disk space, or document size consisting of approximately one thousand bytes. Actual value is 1024 bytes

Kodak PhotoCD
A CD-ROM containing digital images; the CD is created with technology developed by Kodak; each scanned image on the disk is available in five sizes; about 1000 images will fit on a single PhotoCD

Lag Time
Probably the biggest single complaint from digital camera owners is the lag time, the delay from pressing the shutter release to the camera actually taking the shot. This delay varies between camera models, the good news being that manufacturers are addressing this issue and newer digital cameras lag time is decreasing

Lamp
A general term used to decribe the various kinds of artificial light sources used in photography

LAN
An acronym for Local Area Network. A communication networks that's physically connected by cables and confined to a single office or a single building. It enables a group of computer to exchange files and share peripherals

Lantern slides
Is a old term used to described transparencies

Large format camera
Is a general term for any camera having a picture format of 4x5 inches or larger

Lasso
Image editing tool used to select areas of an image for moving or cropping