I'm surprised there has been no flurry of replies to her question. I'll try. Your question is an excellent one because it leads to a discussion of color neg vs color slides (diapositives in Europe). A color slide is the film and camera interpretation of the image photographed. The image is in the positive film dye layers. When viewing by projection or on a light box it remains more or less the same. Many serious digital printers prefer slide film because of fine grain and it inherently tells us what the color balance of the photo is. (Photoshop can change the color and other characteristics if desired-within limits). Color slide film has little latitude (margin for exposure error).
Color negs are analagous to black and white negs but with the complememts of colors in the developed film. For example, a green lawn is magenta in neg film. Color printing papers are also complementary as in b & w printing. Why are color negs orange? Because of technical limitations in the process it is necessary to include an orange mask. The negs are printed either by red, green, blue light exposures or by a single exposure of mixed yellow and magenta light. The color of the light determines the color balance of the print. There is no standard image to serve as a reference as in slide film. The latitude of color negative film is much wider than slides. In a home darkroom the printer has to make many trial and error tests to reach color balance. The balance is always subjective because even when printing my own negs, for example, I might not remember the scene or I might like to alter the balance for some reason. Commercial labs, mini-labs, etc calibrate the printer to a standard provided by the manufacturer. Some mini-labs have standards, or profiles, for many different films, others use a generic profile. When you walk in with a few negatives they just use some profile not knowing much about the negs. Even the same lab will not often make identical prints of a neg on different days. They know brides wear white, grass is green, sky is blue, etc. That is close enough for most consumer prints. Many labs specialize in wedding prints. They calibrate everything to a particular Kodak portrait film used by wedding photographers. I have a complete color neg printing darkroom collecting dust since I changed to digital printing. Color balance is a big challenge to digital printers too, but tools are available to standardize the process and it is much more repeatable than chemical/optical printing. Furthermore, it is just as easy to print slides as color negatives. Before digital printing it was very difficult to print good images from slides. "Newbies" get to go right into digital printing without suffering the trials of chemical color printing. You are lucky. Bill Lawlor
