The Film
Agfa Scala is a black and white reversal film and development process. Instead of creating a black and white negative, Scala produces a positive black and white image. Scala is similar to black and white negative film. A sensitized silver halide layer on the film changes when it is exposed to light. Structurally, Scala is not much different than other black and white negative films. An emulsion is placed on a plastic film bases. Antihalation layers are added to minimize halo effects.
The Process
Scala processing is, in theory, similar to black and white transparency film processing for other brands. The difference is the use of proprietary Agfa chemistry that is no longer commercially available. Some labs, however, have developed chemistry similar to the original Agfa chemistry and offer Scala processing. The steps for processing Scala or another black and white film on which you would like a positive, rather than a negative, image is as follows:
1. Use developer to process the silver halides into a negative image
2. Use a stop bath to halt the developing process
3. Bleach the negative
4. Wash the negative
5. Use a clearing bath to remove clouding caused by the bleaching process
6. Expose the remaining silver halides to light
7. Re-develop the film
8. Use a stop bath to halt the developing process
9. Fix the image to prevent changes when the film is exposed to light
10. Wash and dry the film
Availability of Scala & Processing
Because Agfa is no longer in business, Scala is no longer being made. Currently available Scala is stock manufactured in the late 1990s and early 2000s. Because it is a silver halide based film, properly stored stocks should be good for many years to come.
Because of the dangers involved in the proprietary Scala processing chemistry, you are probably going to be better off having your Scala developed by a professional lab. There are a number of professional labs that offer film processing mailers for Scala.
Tags: black white, black white negative, white negative, Agfa chemistry, Agfa Scala, bath halt, bath halt developing
