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rad imaging
film, rad
| Question | Answer |
|---|---|
| observable difference between x-ray film and photographic film is | thickness and rigidity of the base |
| principal characteristic of the emulsion that makes it particularly x-ray sensitive is its | sensitivity center |
| average silver halide crystal surface size in radiographic film is | 1.0 um |
| radiographic film base appears blue because | a tint is added to make viewing more comfortable |
| celluslose nitrate and cellulose triacetate are used in what component of film | in the film base |
| emulsion that is commonly used in x-ray film consists of | silver halide and gelatin |
| common base in contemporary x-ray film | polyester |
| ensures uniform contact of the emulsion to the base | adhesive layer |
| the overcoat of film usually consists of? | gelatin |
| in film, dimensional stability is the property of maintaining the size and shape of | the base |
| principle purpose of gelatin in film emulsion | support the silver halide crystals uniformly |
| most important property of silver halide in production of the latent image | atomic number |
| x-ray film is sensitive to | x-rays, gamma rays, visible light |
| x-ray film used in radiographic intensifying screens usually has what type of emulsion | emulsion coat on both sides of the base |
| silver bromide is a principal component of what | the silver halide crystals in the emulsion |
| the latent image is formed where | silver halide crystals |
| during the photographic process, metallic silver accumulates where | sensitivity center |
| a collection of silver atoms in the latent image occurs | at the crystal level |
| the sensitivity center is silver __________ | sulfide |
| what additive/impurity is added to emulsion to form sensitivity specs | AgBr (silver sulfide) |
| image-forming and remnant are referred to as | the radiation exiting the patient that is responsible for the latent image formation |
| the interstitial atoms in a crystal of silver halide are | silver, bromide, iodine |
| the formation of the latent image follows what interaction with the emulsion | photoelectric effect |
| theory that best explains the photographic effect | gurney-mott theory |
| the difference between fast film and slow film is silver halide crystal __________ | concentration |
| the spectral response of an emulsion refers to | absorption of visible light |
| calcium tungstate screen emit what type of light | blue and blue-violet light |
| factors that can cause fog | darkroom light leak, background radiation, humidity, temperature |
| orthochormoatic film is sensitive to what light? | green light |
| rare earth films require what color safelight | red |
| describe mammography film | fine grain film used with a screen |
| most rare earth screen emit what color light | ultraviolet, blue, green and red |
| what are the optimal temps and humidity for storing film | 20C/68F or lower with 30-60% humidity |
| film resolution is determined by | size of silver halide crystals |
| smaller crystals result in what type of resolution | higher resolution |
| silver halide crystals are sometimes called | grains/graininess |
| film sensitivity is determined by these factors | silver halide crystal size, number of sensitivity specs and thickness of emulsion layer |
| compare film speed of smaller crystals vs larger crystals | smaller = slower film speed larger = faster film speed |
| compare film speeds related to emulsion thickness of thick vs thin | thick = faster film speed thin = slower film speed |
| what are the primary characteristics of film | resolution, contrast, speed, latitude |
| ability of film to stop light is termed | opacity |
| instrument that provides a readout of the amount of density (blackening) on a film | densitometer |
| type of sensitometric equipment sometimes referred to a step wedge, increasingly thick, uniform absorbers | penetrometer |
| measurement of the characteristic response of film exposure and processing? | sensitomertry |
| as contrast increases what happens to the latitude? | decreases |
| what component makes silver halide crystals photosensitive? | sensitivity specs |
| inherent object unsharpness refers to? | constant motion (ie heart) |
| as the OID increases the detail becomes? | less sharp |
| as the SID increases detail becomes? | sharper |
| as the OID decreases the details become? | sharper |
| the most important consideration in selecting screen-film is? | the spectral absorption characteristics |