Tintoretto, The Last Supper
Church of San Moisè, Venice
One usually trustworthy blogger has identified this as a Tintoretto, and other online sources as by Palma il Giovane. It is not among the Tintorettos or the Palmas at the Web Gallery of Art. It does have the dog and the busy activities seen in Tintoretto Last Suppers.
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Photographed at the church by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.