Julian Sklar spends most of his workday performing on camera. Not for anyone important; the cantankerous artist (played by Ian McKellen), the protagonist of Steven Soderbergh’s new movie, The Christophers , is recording jokey Cameos for eager fans. Facing a ring-lit iPhone, he rambles about his fading career with chipper bumptiousness. Julian, the viewer quickly learns, is guarding a series of unfinished masterpieces in his house that he refuses to complete or sell, and his greedy children want