The Home of the Last Tsar - Romanov and Russian History

This page from the Hagia Sophia website is about the famous 15th century image of angel on the left side of the apse whose face was recently uncovered

Nesterov was one of Empress Alexandra's favorite painters, his picture of the Annuciation hung in the Mauve Room.  He worked for Grand Duchess Elizabeth in her Martha and Mary convent in Moscow.  Here's a bio.