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
Early Netherlandish painting both sides or with the reverse bearing family emblems, crests or ancillary outline sketches. In the case of single panels, the markings on the reverse are often wholly unrelated to the obverse and may be later additions, or as Campbell speculates, "done for the artist's amusement". Painting each side of a panel was practical since it prevented the wood from warping. Usually the frames of hinged works were constructed before the individual panels were worked on. Glue binder was often used as an inexpensive alternative to oil. Many works using this medium were produced but few survive today because of