C-41 / ECN-2 fixer

Description

The final solution of the colour negative processes: it washes out the silver halide and leaves only the dyes in the emulsion. Shared by C-41 and ECN-2.

Why a colour negative is so clear

After fixing there is no silver left in the film at all — the whole image is carried by dyes formed during development. That is why a colour negative looks so clean against the light compared with a black-and-white one.

How long to fix

Under-fixed film yellows and clouds over time as residual halide slowly darkens. Over-fixing colour film is practically impossible, so err on the long side rather than the short.

Questions and answers

Could an ordinary black-and-white fixer do?

At a pinch — it is thiosulphate too. But the proper solution is formulated for the pH and timing of this process.