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Color etchants have a huge potential in industrial applications and numerous investigations have been made to obtain a better understanding of the etching process. However, reproducibility and a solid knowledge of the ongoing processes are still missing. The work presented is a systematic study of the reproducibility of the Beraha color etching with potassium metabisulfite. By in situ observation of the etching process, the different states of the Beraha etching could be followed. It was shown that, at the beginning of the etching of dual-phase steels, the contrasting of the second phase by dissolving the less noble part of the second phase is the predominant contrast. Uncommonly, grain boundaries are hardly attacked. The color development of matrix grains is orientation sensitive and it was shown by comparison with electron backscatter diffraction (EBSD) measurements, that similar orientated grains have similar colors.