fremkalde

Fremkalde is a Norwegian and Danish term used to describe the chemical process of developing exposed photographic film. The procedure converts latent images into visible negatives or positives, depending on the film and processing flow. It is a core step in analogue photography.

In practice, the film is placed in a light-tight developing system and immersed in a developer solution at a controlled temperature, typically around 20°C. Development time depends on film type, emulsion, desired contrast, and agitation style. After development, the film usually passes through a stop bath to halt development, then a fixer to make the image permanent and insensitive to light. The final steps are washing and drying to remove chemicals and preserve the image.

The chemistry of fremkalde involves a developer that contains reducing agents (such as hydroquinone, metol, or phenidone) and often an accelerator to control contrast. The fixer generally contains a thiosulfate compound to dissolve unexposed silver halide. Temperature, chemical activity, and even agitation determine the density and tonal range of the final image, and improper handling can cause fogging or uneven development.

Equipment commonly used includes a darkroom or light-tight developing tank with reels, measuring tools, a thermometer, and a timer. While digital photography has largely supplanted film in many contexts, fremkalde remains fundamental to film-based workflows and continues to be practiced by hobbyists and professionals, often in dedicated labs or home darkrooms. Outputs from fremkalde are typically negatives or positive prints produced from the developed film.