“A self-portrait of David Hockney standing before a work-in-progress while his friend and former assistant, Charlie Scheips, scrutinises the canvas has been acquired by the National Portrait Gallery. The £148,000 purchase is the gallery’s first painted self-portrait of Hockney. Completed two years ago, it was bought from funds raised by ‘gift aid’ in which the public donates money on buying an admission ticket….”