The invention is performed by providing a first flow of water and surfactant, a second flow comprising solvent, base and photographic material, and mixing said first and second streams and either simultaneously or immediately following thereof neutralizing said streams to prevent hydrolysis of a hydrolyzable surfactant and/or premature precipitation of particles before neutralization. The streams then may be immediately treated for formation into photographic materials. In a preferred method the first and second stream may be brought together immediately prior to a mixer with addition of acid directly into the mixer to neutralize the dispersion of fine particles.