Pushing and pulling fi lm

Photographers may push or pull film to alter the resulting contrast. A photographer may also have to push film on location when the ambient light is low. A safety net all photographers can use when using film is the manipulation of processing after exposure. This applies to all film materials. Despite the precision of the camera and metering systems used, human and equipment error can still occur when taking a photograph. If the situation allows bracketing (exposure one and two stops either side of and including normal) is a way of ensuring correct exposure. When there is not the opportunity to bracket exposure and all exposures are meter-indicated exposure (MIE) it is advisable to clip test the film.

Clip test

Clip testing is a method of removing the first few frames from an exposed roll of film and processing as normal (i.e. to manufacturer’s specifications). If these frames appear underexposed, a push process (over processing the film) may improve or compensate for any error in exposure. If overexposure is evident a pull process (under processing) may correct the result. The amount of pushing or pulling required to produce an acceptable result is generally quantified in stops. If an image appears underexposed by one stop push the film one stop. If an image appears overexposed one stop pull the film one stop. Push processing color transparency having correct exposure is also an option. It has the effect of cleaning up the highlights and giving an appearance of a slight increase in contrast. Pushing in excess of what would be required to achieve this can be an interesting exercise. The results can be unpredictably dramatic. Most professional film processing laboratories offer this service.

Normal process One stop push - Fabio Sarraff

Activity 3

Load a camera with color transparency. Deliberately underexpose by one and two stops subjects with average contrast. Clip test the film - normal process. Clip test again - one stop, two stop and three stop push. Assess the result and process the rest of the film at processing levels you determine.