Van Dyck discovery: How to spot a master's artwork
A previously unknown painting by 17th Century master Van Dyck has been identified after being spotted online.
The portrait was previously thought to have been a copy and was in storage at the Bowes Museum in County Durham.
But it was photographed for a project to put all of the UK's oil paintings on the BBC Your Paintings website, where it was seen by an art historian.
It depicts Olivia Boteler Porter, lady-in-waiting to King Charles I's wife, Henrietta Maria.
Culture Show presenter Alistair Sooke and art historian Dr Bendor Grosvenor explain how it is possible to spot an art work by a master.
09 Mar 2013