This exhibition (2010/10/25-30) by Hirano Takako (平野貴子) at Gallery Kobo (巷房) consisted of an interesting set of color prints made from engraved plates. When I met the artist, I asked her how many plates were necessary for the final prints, and she said just one. She went on to explain that the all the colors were applied to the single engraved plate for each picture (see second photo below).
The artist's website (in French and Japanese) is here:
Lyle (Hiroshi) Saxon