Turner Inspired: in the Light of Claude, National Gallery, review Discussions about the formal influence of one artist on another can take you only so far. The real problem with this show is that its emphasis is all wrong. More important than what Turner took from Claude is what he rejected - and how this affected his art. That process of rejection began after Turner's first visit to central Italy in 1819. Then 44 years old, he set off for the south expecting to find the earthly paradise he'd seen in Claude's pictures of Lake Albano, Tivoli, the Tiber Valley and the Campagna. Instead, he discovered that Claude's idealised vision of the classical past was pure fantasy. For all the beauty of the landscape, Turner saw modern Italy as a place of tawdriness, poverty, superstition and decay. Lesser artists, such as his predecessor Richard Wilson, edited the modern world out their Italian views. Turner shows peasants washing their clothes amid picturesque ruins or engaging in exotic Catholic rituals that, to his English eye, looked like new forms of paganism. Particularly after his second journey to central Italy in 1828, Turner went out of his way to show the country as a palimpsest of ancient and modern religions and cultures. This is what makes him a much more complex artist than Wilson, and why his later Italian landscapes are so much greater than those he painted when he knew only the Italy idealised by Claude. The more time I spent in the show the more I drew the opposite conclusion from the one the curators presumably intended for us: crucial though Turner's borrowings from Claude were at the beginning of his career, the further he moved away from Claude's influence the greater his work became. The most beautiful single picture here is the moonlit view of ships on Tyneside, Keelmen heaving in Coals by Night from 1835. Yet again, Turner uses Claude's receding perspective to draw the eye into the distance, with light from the full moon irradiating sky and water. But look at the chromatic drama Turner creates in details such as the firelight illuminating the black hulks of the colliers or the soot rising up to merge into the milky cloud cover. Nothing like this exists in Claude. Before a masterpiece of this calibre, it is hard to regret the nymphs, gods, and goddesses in pictures painted under the spell of Claude. The show is a muddle from start to finish. The best I can say about it is that the curators have borrowed some wonderful pictures to hang alongside much-loved warhorses from the National Gallery and Tate. But in the catalogue essays, art historians are given carte blanche to waffle on for page after page explaining ideas that could be written on the back of a postcard. Don't get me started on the labels: surely there are limits to the number of synonyms curators may use for "soft," "glow" and "light." And you only have to tell us once that Turner left Sunlight Rising through Vapour to the National Gallery in his will. After seeing the exhibition, I found myself writing a single word in my notebook, but that word happens to be the kiss of death for any exhibition: "Why?" Until June 5