A mathematical curve that describes a vector path. In Photoshop Bézier curves are created by plotting anchor points with the pen tool.

A visible stepping of shades in a gradient. A artifact of colour gradation in computer imaging, when graduated colours break into larger blocks of a single colour, reducing the smooth look of a proper gradation.

The PhotoCD image resolution (512 x 1024) that is established for display on current televisions.

The performing of a group of computer tasks at the same time.

Sequential scanning of multiple originals using previously-defined, unique settings for each.

"Named after the French telecommunications technician Baudot. It is the unit used to measure data transfer.

A pattern of red, green, and blue filters on the image sensor's photosites. There are twice as many green filters as the other colors because the human eye is more sensitive to green and therefore green color accuracy is more important.

(binary digit) The basic unit of informa-tion used by computers. It has two -states: on or off.

An image made up of a matrix of dots, or pixels.

When converting an RGB image to CMYK colour mode, black generation refers to the values that are generated for the black plate used in commercial printing.

A colour separation setting that establishes the maximum percentage of black ink in a CMYK image. The setting is made before an RGB image is converted to a CMYK image. The press and paper planned for the publication usually determine the proper black limit setting.

This is the colour that produces colour values of 0, 0, 0 for each of the RGB components when scanned or digitized. Normally, the black point is 0 percent neutral reflectance or transmittance.

A setting in Photoshop that adjusts for differences in black points when converting colours. When selected, the full dynamic range of the source colour space is mapped to the full dynamic range of the destination colour space. When deselected, the dynamic range of the source colour space is simulated in the destination colour space.

"Each pixel (photosite) on a digital camera sensor (CCD/CMOS) has a limit as to how much charge it can store. Blooming (or Streaking) is the name given to an overflow of charge from an over saturated pixel (photosite) to the next on the sensor. This problem is addressed with the addition of "anti-blooming gates" which can be thought of as vertical drain ditches running beside each row of pixels, these gates allow the overflowing charge to run away without affecting surrounding pixels. Anti-blooming gates, while mostly successful (and certainly for more modern sensors) blooming can still be a problem in very extreme exposures (very bright edge against a virtually black edge) and is typically visible as either a vertical streak or white halo extending for several pixels. The effects of blooming often amplify the visibility of chromatic aberrations. Blooming is really good at destroying the detail of leaves shot against a bright sky."

Memory in the camera that stores digital photos before they are written to the memory card.

Selectively darkening part of a photo with an image editing program.

The ability of a camera to take one picture after another as long as you hold down the shutter release button.

A unit of information equal to eight bits.