Kodak High Concentrate Developer is a liquid concentrate for black and white film, 1 litre. It is the official successor to the legendary HC-110, on a new 2025 formula.
What it is for
It was created as a fast developer for press photographers and ended up somewhere else entirely — in large format and among Zone System practitioners. The reason is single: negative contrast can be controlled here very precisely, by dilution and time, which is exactly what the Zone System was invented to exploit. The formula is compensating, with the finest grain and full use of film speed.
How to dilute it
It is a one-shot developer: mix the working solution, use it, discard it. That is the most predictable way to work — every film is developed in fresh solution, so times need no extending from roll to roll.
Storage
Sealed concentrate keeps well but dislikes air: the emptier the bottle, the faster it oxidises. Decant the remainder into a smaller bottle, or displace the air — that is what gets a concentrate to its last measure.
How it compares
The main alternative is Bellini EURO HC, cheaper and very close in intent. What this concentrate has is the enormous body of published times accumulated over the decades of HC-110: for almost any film at any dilution, somebody has already measured it.
