File format used for saving levels and curves in histograms in Adobe Photoshop.
A positive picture made by the collodion process on glass and viewed against a dark background.
An image that is formed by mercury vapor on a silver-coated copper plate.
De-screening mode:
This practice helps conceal the halftone dots (ink dots ) which result from the technique used during printing.
An early type of photograph that is a direct positive image made on a sensitized piece of enameled tin or iron.
Joint Photographic Experts Group. A lossy compression technique used for saving images and photographs. This compression method reduces the file size of an image but reduces also its quality.
Newton's Rings:
Concentric ring patterns (dark and bright bands) may appear while scanning negatives, glass negatives, transparencies and lantern slides. These rings are caused by the interaction of light waves reflecting on two glossy surfaces - on convex an one flat - and the air pockets between them.
Initial Image File. Contains minimal processed data from a digital camera or a scanner. Before any manipulation can be done, the RAW file must be converted into another format.
Red, Green, Blue. The main colours in photography.
Tagged Information File Format. A lossless image format developed for the purpose of storing high-resolution bit-mapped greyscale, and colour images.
Horizontal and vertical measurements of an image expressed in pixels.
lantern slide:
A transparent image on glass, approximately 3½ X 4 inches, that is intended to be viewed by projection. Some lantern slides may be hand-painted.
A unit of measurement used for spatial resolution of a digital image. Resolution is often referred to as dots per inch or DPI. This term is appropriate when describing printer resolution. In common usage the terms, PPI and DPI are used interchangeably; however, since image files are composed of pixels, PPI is a more accurate term for digital images and has been used in this document.
reflective mode:
Scanning process where the light bounces on the document surface. Example: scan of a photographic print, a paper document, etc.
transparency mode:
Scanning process where the light goes through the document. Example: used when scanning a slide, a film, etc.

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