GLOSSARY
BRIGHTNESS | The lightness or darkness of the image. |
CHANNEL | The component of an image. Your scanned image has three |
| channels: red, green, and blue (RGB). |
CONTRAST | The gradation of shades in an image. A high contrast image |
| has very dark areas and bright areas without many middle |
| shades. A low contrast image has many tones that are close to |
| the same brightness. Low contrast images are often described |
| as looking ‘flat’. |
CROP | To trim and delete the unwanted edges of the image. |
DPI | Dots (pixels) per inch. |
EMULSION SIDE | The side of the film coated with the photographic material. |
GAMMA | The contrast of only the middle tones. |
HIGHLIGHTS | The lighter areas of the image. |
HISTOGRAM | A graph showing the amount of each level of the 256 |
| brightness levels. |
INTERPOLATION | A form of adding new pixels in an image when resampling up. |
JPEG | The JPEG (Joint Photographic Experts Group) compression |
| standard is capable of producing a high compression ratio |
| while maintaining image quality. JPEG is a widely supported |
| image file format. |
MIDTONE | The middle shades of an image, in between light and dark. |
NEUTRAL | Having no colour cast, such as black, white, or gray. |
PICT | (Macintosh operating system only) The PICT graphic file format |
| uses a lossless compression scheme and is compatible with |
| many Macintosh applications. |
PIXEL | Abbreviation for picture element. The dots that make up an |
| electronic image. |
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