Bromoil bleach

Description

The bleach that bromoil begins with: it removes the silver from an ordinary print and hardens the gelatin in proportion to the density that was there. The image is then inked with oil paint.

What it actually does

After bleaching, almost no silver remains — but the gelatin is hardened more in the shadows than in the highlights and takes up water differently. A soaked print accepts greasy ink where the gelatin is drier, that is, in the shadows. That relief is what the whole process rests on.

Which paper works

Not every one: modern papers with little gelatin and a pre-hardened emulsion give no relief. You need fibre-based paper without excessive hardening — the main constraint on bromoil today.

Questions and answers

Could a sepia bleach be used?

No. A sepia bleach does not harden the gelatin, and without hardening there is no relief — the ink would take evenly everywhere.