Imperial diptych Imperial diptych In Late Antiquity, an imperial diptych is a theoretical type of ivory diptych, made up of two leaves of five panels each and each with a central panel representing the emperor or empress. They are so-named in contrast to consular diptychs. They were produced as unique examples, whereas each consular diptych was produced in large numbers to offer to the emperor on certain occasions, principally a nobleman's entry to the consulship. No complete example of an imperial diptych survives and so their existence is contested. The ivories specialist R. Delbrück has theorised that the 19 surviving fragments of
Heller Altarpiece Heller Altarpiece The Heller Altarpiece was an oil on panel triptych by German Renaissance artists Albrecht Dürer and Matthias Grünewald, executed between 1507 and 1509. The artwork was named after Jakob Heller, who ordered it. Dürer painted the interior, Grünewald the exterior. In 1615, Dürer copyist Jobst Harrich painted a duplicate, which is now at the Städel of Frankfurt. The side panels, executed by Bosch's workshop basing from his drawings, are at the Staatliche Kunsthalle of Karlsruhe. The painting was commissioned by Frankfurt merchant Jakob Heller, for the Dominican church of the city. In 1615, the central panel, the only