Pushing two stops on a grey morning
The light on the breakwater before nine is flat and about three stops short of what a 400-speed film wants at a hand-held shutter speed. Rating the roll at 1600 and extending development is the usual answer, and it works, with two costs worth knowing in advance.
What changes
Shadows do not gain detail from longer development; they were never exposed. What grows is contrast in the mid-tones and highlights, and grain along with it. On an overcast day that extra contrast is welcome. Under direct sun it is not, and a one-stop push is the limit.
Times that worked
| Rated at | Dilution | Time at 20 °C | Agitation |
|---|---|---|---|
| 400 | 1+1 | 11 min | 10 s each minute |
| 800 | 1+1 | 14 min | 10 s each minute |
| 1600 | stock | 12 min 30 s | 10 s each minute |
Treat these as a starting point. Water hardness, the thermometer and the way the tank is turned all move the result by more than the difference between two published charts.