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Trial and Error Printing
On-Easel  Analyzers

Photography (Basic) - Introduction to photography and other graphic techniques
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Figure 12-5.–On-easel color analyzer. 302.261 negative to be printed is then read on the densitometer and  these  densities  are  subtracted  from  the  total  density values  of  the  standard  negative  (negative  reference patch  and  enlarger  filter  pack).  This  method  of evaluation does not indicate directly the required exposure for the production print, but the production print exposure can be estimated closely by using the standard negative exposure and compensating for any changes to the filter pack. An example on how this off-easel evaluation system operates is as follows: Gray  patch  of  standard negative =   47C   51M   50Y Established  filter  pack  for standard  negative =    0C    47M    34Y Sum: 47C 98M 84Y Subtract gray patch of production  negative –44C  63M  49Y Difference: 03R 35G 35Y To  illuminate  neutral  density –    03    03    03 Production negative filter pack 0C 32M 33Y A reflection densitometer also can be very useful in color  print  evaluation.  A  reflection  densitometer  can  be used to match an earlier printed print with the color print you  are  currently  printing.  To  use  a  reflection densitometer as an aid in color printing, you must compare or read a reference area on your test print. This is particularly useful when you are making a color print with neutral areas. As you know, black, gray, and white have approximately equal portions of red, green, and blue. By taking a reflection densitometer reading directly from one of these neutral areas (such as a gray card, the side of a ship, or part of a gray aircraft), you can determine what color and the amount of that color in  excess.  To  change  your  filter  pack  for  print corrections, you must take one half of the density value as read from the densitometer and either add or subtract that value from your filter pack; for example, you take a reflection densitometer reading from a gray patch on your color test print. Your density readings are 50R, 50G, and 70B. The densitometer indicates that your test print is high by 20B (too much yellow dye). To adjust the filter pack, you should add CC10Y to your filter pack for subtractive printing or add CC10B on an additive printer. Another off-easel color evaluation system is a color video analyzer. This system scans the color negative and is viewed directly on a color monitor. The image on the monitor can be manipulated until the proper color balance,  density,  and  image  size  are  achieved.  The 12-12







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