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Photography (Basic) - Introduction to photography and other graphic techniques
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The chemistry most commonly used in the Navy for color  paper  processing  is  Kodak  Ektacolor  RA Chemicals for Process RA-4. The RA-4 process is a washless process that consists of color developer, bleach/fix, and stabilizer. The total processing time for the RA-4 process is about 4 1/2 minutes. Transparencies  that  are  old  or  stored  under  adverse conditions are likely to fade to some degree. This fading may not have been equal overall. That can create problems in printing. Generally, slide duplicates vary widely in quality and do not make high-quality color prints. MAKING TRANSPARENCIES FROM COLOR   NEGATIVES You can make brilliant color transparencies from color negatives as easily as you made color reflection prints  by  using  color  printing  materials  on  a  transparent film  base.  These  transparencies  are  of  excellent  quality. This allows you the option of making them larger, smaller,  or  the  same  size  as  the  original  negative. There  are  several  direct  positive  materials  available for making color prints directly from color slides. Kodak Ektachrome 22 paper is a reversal color paper that, when exposed to a slide, produces a positive color image of the slide. Kodak Ektachrome 22 paper is processed in Kodak  Ektachrome  R-3000  chemicals.  Consult  the Photo-Lab-Index  for  the  most  updated  information concerning  these  processes. Several materials are available for making color transparencies from color negatives. Two of the most common are Kodak Duratran RA and Kodak Duraclear RA  display  materials.  These  materials  allow  you  to make  large-display  transparencies  from  color  negatives. Another way to make full-color prints directly from color  transparencies  is  by  the  dye  destruction  color process. At the time this training manual was written, Cibachrome products are the only direct positive color materials  manufactured  using  this  process. The Kodak Duratran RA and the Duraclear RA transparency  materials  can  be  printed  using  the  same methods,  printing  equipment,  and  processing  chemicals as Duraflex RA print paper. Both the transparencies and paper are processed using Kodak Ektacolor RA-4 chemicals;  however,  the  transparency  materials  require a  longer  processing  time.  The  Kreonite  Model  KCP-16 allows  for  this  longer  processing  time.  By  flipping  a switch,  you  can  slow  down  the  processor,  allowing  for a  longer  processing  time. 12-14 Cibachrome silver-dye-bleach materials consist of a  white  opaque  support,  coated  with  light-sensitive emulsion layers on one side and a matte, anticurl gelatin on  the  opposite  side.  This  white  pigmented  plastic  film base has a similar appearance to paper but is actually a film, much like color slide materials-the emulsion layers  are  arranged  in  the  same  order  as  color transparency  (slide)  materials  (including  the  yellow filter  layer). When printing color transparency materials, you must use a black easel. Because these materials do not have a paper backing, light is transmitted through the material and reflects back when a black easel is not used. All other printing steps are the same in printing color paper  and  color  transparency  materials.  Consult  the Photo-Lab-Index for starting exposure and filter pack settings. Unlike conventional color paper processes where dyes  are  formed  from  color  couplers  during  processing, dyes in Cibachrome materials are incorporated in the blue,  green,  and  red  light-sensitive  layers  during manufacturing. These cyan, magenta, and yellow dyes are designed to be destroyed when processed. Red exposure is intended to cause the destruction of cyan dyes, green exposure leads to the destruction of magenta dyes, and blue exposure sets up the destruction of yellow dyes. COLOR PRINTS FROM COLOR TRANSPARENCIES Color  prints  can  be  made  directly  from  color transparencies (slides) without the time and expense of making an internegative, but the quality of a print can only be as good as the quality of the transparency from which the print is made. Originals that are poorly exposed or processed or are damaged or dusty do not provide  satisfactory  prints. The processing of Cibachrome materials involves four chemical steps: black-and-white   developer, bleach,  fixer,  and  stabilizer.  In  the  black-and-white developer, the exposed silver halide crystals are reduced to  metallic  silver.  When  the  silver  halides  in  the emulsion layers are converted to metallic silver, the dyes present  in  the  emulsions  are  fragmented.  In  the  bleach, the silver image is converted back to silver salts (halides),  and  the  dye  fragments  are  made  either colorless or water soluble. The unwanted silver salts (halides) are then removed in the fixer. The stabilizer keeps  the  remaining  color  dyes  more  permanent.







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