Film Push / Pull: Two Official Examples of Kodak ECN-2 and TRI-X 400

Push and Pull are compensating processes, not universal formulas

Kodak's definition of ECN-2 is: push compensates for underexposure by increasing development; pull compensates for overexposure by reducing development. The specific times depend on the particular film, processing line, temperature, and machine conditions, and different processes cannot be applied interchangeably. [G-PP-01]

Color Movie Negative: Kodak ECN-2 Laboratory Starting Conditions

The Kodak page lists the normal ECN time as 3:00; Pull 1 as 2:30, Push 1 as 3:40, and Push 2 as 4:40, all run at 106°F (41.1°C). Kodak refers to these as laboratory starting points, and they can be adjusted according to LAD density, not as home black-and-white tank processing formulas. Push compensation is not complete and may increase contrast, color shift, and grain. [G-PP-02, G-PP-03]

Black-and-White Film: Kodak TRI-X 400 Example

Kodak recommends TRI-X 400 / 400TX for push. F-4017 indicates that one stop underexposure can be developed with normal time but with slight shadow detail loss; two to three stops push require increased development time, adding contrast/grain and further loss of shadow details. As a specific example: EI 1600, D-76 small tank, 20°C, agitation every 30 seconds, Kodak lists 9½ minutes. Other chemicals, temperatures, tank types, and agitation methods should refer to their respective tables; test rolls should be used first. [G-PP-04, G-PP-05, G-PP-06]