light-sensitive  materials,  and  lighting  conditions commonly  used  in  your  facility;  for  example,  when awards presentations are commonly photographed using  syncro-sun  techniques  with  a  medium-format camera  and  Kodak  VPS  film,  then  your  standard negative should be taken under the same conditions. The same applies for studio portraits, indoor on-camera flash photography, and so forth. A basic enlarger filter pack should  be  determined  for  each  negative. TRIAL-AND-ERROR PRINTING Few characteristics are exactly the same in two color negatives. Even when the subject matter is similar, differences  can  be  caused  by  normal  manufacturing variations from one emulsion to another, adverse conditions before exposure, illumination of different color quality, variance in sensitivity with changes in illumination  level  and  exposure  time  (reciprocity effect),  adverse  storage  conditions  between  exposure and  processing  (latent  image  loss),  and  nonstandard processing   conditions. Most color negatives of the same subject that are exposed under similar conditions print similarly, but not identically.  Differences  may  result  from  variations  in lighting conditions (time of day, sky conditions, etc.), film  emulsions,  film  processing,  or  other  factors.  These differences are normal and should be expected. The standard  negative  provides  a  good  starting  point  for future  printing  requirements. For  example,  you  made  an  excellent  8x10  print from the standard negative with a filter pack of 40M + 60Y and exposed the print for 10 seconds at f/5.6. The enlarger settings should remain the same as a starting point for similar negatives, providing the same type of paper  is  used.  For  a  particular  production  negative,  you may find it necessary to add a 10M filter to the pack and adjust the printing time to 11 seconds to compensate for the differences between the new negative and the standard negative. In other words, the new negative may print differently from the standard negative by a 10M filter  and  a  10-percent  increase  in  printing  time. The amount and types of color equipment you use depend on the volume of color production of the imaging facility where you work. A photo lab that makes occasional color prints probably uses only a standard negative and color printing viewing filters. Larger Navy imaging facilities that produce large quantities of custom color printing may use evaluation methods involving   instruments,   such   as   color   analyzers, densitometers,  and  other  electronic  devices. COLOR  ANALYZERS Color  analyzers  operate  by  comparing  a  standard negative  to  production  negatives.  For  successful negative evaluation, the reference areas must have the same subject matter in all the negatives; for example, a gray card included in the picture, a flesh tone, the highlighted area of an aircraft wing, or a neutral area of a  ship,  all  provide  a  suitable  reference  area.  In portraiture, a medium-flesh tone is often selected In other fields of photography, you should either include a gray card in the scene or expose an additional negative replacing the subject with a gray card. In the latter case, the  negative  with  the  gray  card  is  used  only  for evaluation purposes and is replaced by the subject negative  when  the  print  is  made. When a skin tone is used instead of a gray card in portrait  negatives,  the  color  analyzer  tends  to  reproduce all  skin  tones  the  same  as  the  standard  negative regardless  of  variations  in  skin  color  or  lighting. Similarly, all images of a gray card tend to be printed alike regardless of the position of the card relative to the main light. Color analyzers are used to reduce the waste that is produced  through  the  trial-and-error  method  of  color printing. The standard negative is used as a reference when color analyzing instruments are used. There are two categories of color analyzers: off-easel and on- easel. Off-Easel  Analyzers Off-easel   color   evaluation   is   performed   by measuring or evaluating the color negative before it is placed in the enlarger. Commonly in Navy imaging facilities, off-easel evaluation is accomplished using a densitometer.   The   main   advantage   of   using   a densitometer is you can service a number of enlargers. That is especially useful when you cannot have on-easel analyzers for each color enlarger. Another advantage, off-easel evaluation can be done under normal room lighting  conditions. To set up an off-easel evaluation system, you must first read the density of the reference patch from your standard  negative  on  a  transmission  densitometer.  You read the reference patch through a red, green, and blue filter. The densitometer provides you with direct density reading of the cyan, magenta, and yellow dyes present in the reference patch. The values that you read from the reference pack are then added to the known standard negative  filter  pack  of  the  enlarger.  The  production 12-11