SPUR HCT is a high-contrast liquid concentrate, 500 ml, for black and white films and papers in technical work.
What it is for
A dedicated formula for work that needs a hard black-to-white transition with no mid-tones: reproducing drawings and line art, making masks and matrices, technical photography. It works on film and on paper alike.
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
Rollei RHC in this same catalogue is close in purpose and cheaper. SPUR traditionally trades on precision of result; the deciding question is whether you specifically want SPUR's own time tables.
