A
Adjustment layers: Non-destructive (always editable) image adjustment placed on a layer.
Adobe gamma: A calibration and profiling utility supplied with Photoshop.
Aliasing: The display of a digital image where a diagonal or curved line appears jagged due to the square pixels.
Anti-aliasing: The process of smoothing the appearance of lines in a digital image.
Artifacts: Pixels that are significantly incorrect in their brightness or color values.
B
Bit: Short for binary digit, the basic unit of the binary language.
Bit depth: Number of bits (memory) assigned to recording color or tonal information.
Blend mode: The formula used for defining the mixing of a layer with those beneath it.
Brightness: The value assigned to a pixel in the HSB model to define the relative lightness of a pixel.
Byte: Eight bits. Standard unit of data storage containing a value between 0 and 255.
C
CCD: Charge coupled device. A solid state sensor used in digital image capture.
Channel: A division of color or luminance data.
Clipboard: The temporary storage of something that has been cut or copied.
Clipping group: Two or more layers that have been linked. The base layer acts as a mask limiting the effect or visibility of those layers clipped to it.
Cloning tool: A tool used for replicating pixels.
Color Picker: Dialog box used for the selection of colors.
Color fringing: Bands of color on the edges of lines within an image.
Color gamut: The range of colors provided by a hardware device, or a set of pigments.
Color management: A system to ensure uniformity of color between the subject, monitor display and final print.
Compression: A method for reducing the file size of a digital image.
Constrain proportions: Retain the proportional dimensions of an image when changing the image size.
Continuous tone: An image containing the illusion of smooth gradations between highlights and shadows.
Contrast: The difference in brightness between the darkest and lightest areas of the image or subject.
Crash: The sudden operational failure of a computer.
Crop: Reduce image size to enhance composition or limit information.
Curves: Control in the full version of Adobe Photoshop only for adjusting tonality and color.
Default: A ‘normal’ or ‘start’ setting as chosen by the manufacturer or user.
Depth of field: The zone of sharpness variable by aperture, focal length or subject distance.
Download: To copy digital files (usually from the Internet).
Dpi: Dots per inch. A measurement of resolution.
E
Editable text: Text that has not been rendered into pixels.
Exposure: Combined effect of intensity and duration of light on a light sensitive material or image sensor.
Exposure compensation: To increase or decrease the exposure from a meter-indicated exposure to obtain an appropriate exposure.
F
Feather: The action of softening the edge of a digital selection.
File format: The code used to store digital data, e.g. TIFF or JPEG.
File size: The memory required to store digital data in a file.
Format: The orientation or shape of the image or the erasure of a memory device.
Freeze: Software that fails to interact with new information.
G
Galleries: A managed collection of images displayed in a conveniently accessible form.
Gaussian Blur: A filter used for defocusing a digital image.
Gigabyte: A unit of measurement for digital files, 1024 megabytes.
Grayscale: An 8-bit image used to describe monochrome (black and white) images.
H
Hard drive: Memory facility that is capable of retaining information after the computer is switched off.
High Dynamic Range (HDR): A subject brightness range that exceeds the ability of the capture medium (film or sensor) to record both the highlight and shadow information simultaneously
Highlight: Area of subject receiving highest exposure value.
Histogram: A graphical representation of a digital image indicating the pixels allocated to each level.
Hue: The name of a color, e.g. red or green.
I
Image size: The pixel dimensions, output dimensions and resolution used to define a digital image.
Interpolation: Increasing the pixel dimensions of an image by inserting new pixels between existing pixels within the image.
ISO: International Standards Organization. A numerical system for rating the speed or relative light sensitivity of a film or sensor.
J
JPEG (.jpg): Joint Photographic Experts Group. Popular but lossy (i.e. destructive) image compression file format.
Kilobyte: 1024 bytes.
Lasso Tool: Selection tool used in digital editing.
Latitude: Ability of the film or device to record the brightness range of the subject.
Layer mask: A mask attached to an adjustment layer that is used to define the visibility of the adjustment. It can also be used to limit the visiblity of pixels on the layer above if that layer is grouped or clipped with the adjustment layer.
Layers: A feature in digital editing software that allows a composite digital image where each element is on a separate layer or level.
Levels: Shades of lightness or brightness assigned to pixels.
LZW compression: Lossless compression that may be used in the TIFF format.
M
Magic Wand Tool: Selection tool used in digital editing.
Marching ants: A moving broken line indicating a digital selection of pixels.
Marquee Tool: Selection tool used in digital editing.
Megabyte: A unit of measurement for digital files, 1024 kilobytes.
Megapixels: More than a million pixels.
Memory card: A removable storage device about the size of a small card.
Minimum aperture: Smallest lens opening.
Mode (digital image): The tonal and color range of the captured or scanned image.
N
Noise: Electronic interference producing speckles in the image.
O
Opacity: The degree of non-transparency.
Opaque: Not transmitting light.
Optimize: The process of fine-tuning the file size and display quality of an image.
Out of gamut: Beyond the scope of colors that a particular device can create, reproduce or display.
P
Pixel: The smallest square picture element in a digital image.
Pixellated: An image where the pixels are visible to the human eye and curved or diagonal lines appear jagged or stepped.
Primary colors: The three colors of light (red, green and blue).
RAM: Random access memory. The computer’s short-term or working memory.
Reflector: A surface used to reflect light in order to fill shadows.
Resample: To alter the total number of pixels describing a digital image.
Resolution: A measure of the degree of definition, also called sharpness.
RGB: Red, green and blue. The three primary colors used to display images on a color monitor.
Rubber Stamp: Another name for the Clone Stamp tool used for replicating pixels.
S
Sample: To select a color value for analysis or use.
Saturation (color): Intensity or richness of color hue.
Save As: An option that allows the user to create a duplicate of a digital file with an alternative name or in a different location.
Scale: A ratio of size.
Scratch disk: Portion of hard disk allocated to software such as Elements to be used as a working space.
Screen redraws: Time taken to render information being depicted on the monitor as changes are being made through the application software.
Sharp: In focus. Not blurred.
Sliders: A sliding control to adjust settings such as color, tone, opacity, etc.
Stamp Visible: The action of copying the visible elemnts from a number of layers and pasting them on to a new layer.
System software: Computer operating program, e.g. Windows or Mac OS.
T
TIFF: Tagged Image File Format. Popular image file format for desktop publishing applications.
Tone: A tint of color or shade of gray.
Transparent: Allowing light to pass through.
U
Unsharp Mask: See USM.
USM: Unsharp Mask. A filter used to sharpen images.
W
Workflow: Series of repeatable steps required to achieve a particular result within a digital imaging environment.
Z
Zoom Tool: A tool used for magnifying a digital image on the monitor.