Wednesday 21 December 2011

Did you know?... Sepia

Angry sea bird spotting a cuttlefish
Graphite sketch by Estelle Rocca-Serra
We’re all familiar with the romantic sepia tone of old photographs, but the name actually comes from “Sepia Officinalis”, the latin name of the common cuttlefish.

Sepia is a natural dye found in the ink bags of the cuttlefish, who, when under threat, releases the dark brown ink to take cover.

To be honest if I was feeling threatened by this kind of angry looking predator, I’d release some ink too!

In the late 18th century a technique was developed where those bags were dried and the ink extracted in concentration high enough to use in paint, particularly in watercolour.

The colour is a very dark brown, almost black. Each species of cephalopod produces slightly differently coloured inks; for example the octopus produces black ink and squid ink is blue-black. Only the cuttlefish ink is used as art material.

Sepia drawings were much celebrated towards the end  the 18th century, but Sepia being a dye, not a pigment, fades over time when in contact with light, so most of those drawings are now a subtle bleached yellow-brown memory.

We now have modern pigments which are permanent and come in the same range of colour, to replace this natural ink.

Stay tuned...

Sources: The materials and Techniques of paintings, Kurt Wehlte; Wikipedia

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