Enlarged Negatives: Theory & Practice

Because we need to work from a positive that is lower in contrast than a normal negative designed for printing, and we need to generate a final negative that is higher in contrast than a normal printing negative, conventional film developers are often incapable of generating sufficient contrast before general fogging sets in, lowering contrast. The solution to this problem is to use developers capable of generating higher contrast negatives than normal film developers. For instance, if we develop a negative in HC-110 for ten minutes and it is not contrasty enough for its intended use, increasing the development time will likely result in chemical fog rather than increased contrast. The next developer to try is D-19 which is capable of generating a higher contrast negative than HC-110. If ten minutes in D-19 isn't contrasty enough, D-11 can make a contrastier negative than D-19. In the unlikely event that D-11 isn't contrasty enough, there is D-8, an extremely contrasty developer. With these four developers you should be able to handle any situation. These are all comercially available Kodak developers and the formulas are published so they can also be mixed from scratch.

Once the final negative is generated there are other modifications that can be employed to get us closer to the perfect negative, which will affect local areas or the entire negative. Selenium toning the negative will result in a contrast increase, with more effect to the highlights. Selenium toner can be applied locally with a brush to increase density. Detail can be enhanced by retouching with a soft lead retouching pencil. The entire negative can be chromium intensified, or bleached and redeveloped in a pyro based developer. New coccine can be applied to lighten areas in the print. These controls will be discussed in more detail later.