About Silver Halide

What this site is

Silver Halide is a reference and a set of tools. It documents the equipment and the chemistry of analogue photography, and it provides four interactive simulators and three calculators for the parts of the process that are hardest to learn from text alone.

The site covers 28 pieces of equipment across five stages of the process, from the emulsion in the camera to the acid-free box the negatives end up in.

What this site is not

It is not a shop. Nothing here is for sale, no product is sponsored, and no brand has paid for placement. Where a manufacturer is named — D-76, Rodinal, Tri-X, HP5 — it is because the product is a useful reference point, not because of any commercial relationship.

It is not a guarantee. Photography is physical, and chemistry behaves differently in different water, at different altitudes and with different hands. Every time and every dilution on this site is a starting point. The data sheet that came with your film and your developer outranks anything written here.

How the numbers were produced

Development times come from published manufacturer data sheets, rounded to the nearest half minute and stated for a small inversion tank at 20 °C. Temperature compensation uses the widely published approximation of roughly four percent per degree Celsius away from 20 °C. Push and pull compensation uses roughly eighteen percent per stop pushed and thirteen percent per stop pulled.

None of these are laws of nature. They are starting points for a personal calibration, which is the only calibration that matters.

Editorial independence

The site accepts no advertising and no affiliate revenue. If that changes, this page will say so before anything else does.

Accessibility and performance

The interactive tools are progressive enhancements. Every one of them falls back to a written procedure or a static illustration when WebGL or Canvas is unavailable, and all animation respects the operating system's reduced-motion preference. The 3D libraries load only on the four studio pages — never on the home page or in the reference sections.