screen/halftone density
screen/halftone density (In French densité tramé) integrally measured density of halftone printed surfaces.
screen
screen (In French trame) frequency-dependent-periodical (amplitude modulated, AM) or stochastically distributed (frequency modulated, FM) or AM/FM hybrid (XM, cross-modulated) structure of printed picture elements.
screen angle
screen angle (In French angle de trame) preferred direction of periodical halftone dots; four-color combination printing: 30° sequences for the crossline screen (0°/15°/45°/75°), 60° sequences for the chain dot (0°/15°/75°/135°), duplex printing 75° for the light and 135° for the dark color. In hifi color systems, the additional colors take over the screen angle of one of the replaced combination inks.
scotopic vision
scotopic vision (In French vision scotopique/nocturne) vision adapted to the dark, with the rods on the retina.
SCOT, Standard Color of Textile
SCOT, Standard Color of Textile (In French DIC, Dictionnaire Internationale de la Couleur) international color index created for the textile industry, which among other things the state flags of all nations are oriented towards. The dyeing references (2300 cotton textiles, 2568 polyester fabrics, 1100 balls of wool), which are based on the Munsell color ordering system, have distinctive codes instead of fashionable color names.
scattering power
scattering power (In French pouvoir de diffusion) property of pigments to reflect incident light diffusely.
scattering
scattering (In French diffusion) diffuse distribution of light rays.
scatter/random proof
scatter/random proof (In French épreuve groupée) for reasons of material savings, joint digital proof of images from different jobs on one and the same proof sheet.
saturation
saturation (In French saturation) chromaticness in terms of brightness; in CIELAB the chromaticness C* describes the colorfulness of a color shade in terms of the chrominances a* and b*, that is, the distance from the achromatic axis L*, and saturation S* plus the concrete brightness level L* of this color shade.
runability
runability (In French roulabilité) the total effect of all printing ink properties with respect to drying behavior, consistency, wetting ability, emulsifying qualities and propensity to cause printing problems.
rub/scratch-off ink
rub/scratch-off ink (In French encre grattable) opaque latex printing ink, in some cases with metallic-effect pigments, which is printed on a previously applied release varnish to guarantee a reading protector or its removal through scratching off; can be implemented in flexo printing, screen printing, but also with inline varnishing units; rub/scratch-off ink can be overprinted.
rods
rods (In French bâtonnets de la rétine) retinal receptors responsible for scotopic vision.
RIP, raster-image processor
RIP, raster-image processor (In French processeur de rastérisation d’image, générateur d’image tramée) workflow component in which rasterization is carried out for the illustration of printing plates or digital print output; in the PostScript workflow (obsolete) possible location for the implementation of the last color transformation within the framework of In-RIP separation.
RIMM-RGB, Reference Input Medium Metric RGB
RIMM-RGB, Reference Input Medium Metric RGB RGB working color space (PIMA 7666) specially developed for scene-related raw color image data, i.e. digital camera raw data (RAW) with defined conversion into CIELAB.
Richter’s law
Richter’s law (In French loi fondamentale de Richter) with respect to the retinal receptor types, Manfred Richter defined as follows in 1948: “The brightness-adapted trichromatic eye evaluates incident radiation according to three independent spectral response functions in a linear and constant manner, whereby the individual responses add up to one indivisible overall response.”
rheology
rheology (In French rhéologie) theory of flow properties (consistency, stringing, thixotropy, viscosity, stickiness, tack); important for the wetting and adhesion of the printing ink on the substrate and on each other.
RGB
RGB (In French RVB) color space model for additive color mixture (see there).
retina
retina (In French rétine) location of the color stimulus input (color perception) in the eye. The retinal receptors are the cones (uvulas, cônes) for trichromatic daytime vision and the rods (bâtonnets) for monochromatic scotopic vision. Most cones are concentrated in the macula lutea (tache jaune), and in the middle is the fovea (fovéa), the point of sharpest vision. The receptorless entrance of the optic nerve is called the blind spot (point aveugle).
resolution
resolution (In French résolution) number of pixels per unit of length (pixels per inch, ppi) of input devices (camera, scanner), of the dots (dots per inch, dpi) of output devices (desktop printers, digital printing systems, plate imaging) or of the screen elements (“screen ruling” in lines per centimeter, L/cm, 1/cm, lines per inch, lpi) of print subjects. Resolution, screen ruling and grayscale are related by the following formula: (resolution [ppi, dpi] / screen ruling [lpi])²…
repeatability
repeatability (In French répétabilité) statistically verifiable repetitive accuracy.