There’s been a minor name change, it’s true, yet our annual watercolour competition, now the RWS/Sunday Times Watercolour Competition, now in its 21st year (and the only competition — plus exhibition — of its kind in the world), remains largely the same. Among the other slight alterations, the most obvious is in the allocation of prizes. We are now offering a first prize of £15,000, a second worth £7,000, plus £1,500 for the best submission by an artist under 30. There is also an entirely new award, the Penguin Classics Prize for Cover Art. This amounts to £1,500, and the winner also receives a valuable commission to provide the artwork for the cover of one of the Penguin Classics.

The judges, confronted by so many outstanding paintings this year, decided they should introduce a Highly Commended category for the first time. Sadly, there is no money for the four artists whose entries were singled out in this way, but at least they now know who they are. They were separated from the winners by a margin as slim as a sheet of 140lb Whatman paper.

Some of the judges have changed, too. While Professor Brian Allen of the Paul Mellon Institute remains the chairman, one new judge is Richard Sorrell, the president of the Royal Watercolour Society; another is that wise and enthusiastic foe of the conventional, Anthony Green RA, the painter. Penny Johnson, director of the Government Art Collection since 1997, happily returns to the judging panel, which also includes me.

In another move, the show is no longer staged in the Mall Galleries (whose position within sight of Buckingham Palace is grander than its rather bland spaces), but is now hosted by the Royal Watercolour Society at the Bankside Gallery, the society’s home near Tate Modern. The space here cannot accommodate quite so many pictures as the Mall Galleries, and though the difference is negligible, the judges did have problems whittling down the entries to a number of pictures comfortable enough for Allen to hang without giving everyone claustrophobia.

If the judges took longer than usual to select the works for the exhibition, we quickly made up their minds about a shortlist of prizewinners. Although choosing the absolute winner was subsequently no problem, the recipients of the other prizes were much harder to pick. The quality of Jennifer McRae’s portrait of her husband, David by the Window, Spencer’s Belle Vue, shone out from the first.

Sorrell described this large, bright but unassertive painting as “amazing, strong, subtle and magnificent”, and we all agreed. Green enthused about the “purity of the watercolour technique, and the consequent luminosity achieved”, again to universal agreement. McRae, the worthy winner of the first prize, explains that her picture “is all about the quality of light in this particular room. It is quite unique, gentle and opaque. I found myself focusing on this element and being less concerned with particular features and small detail”.

Cameron Galt’s attention-grabbing still life, Late Saturday Morning, similarly took our fancy right from the beginning. Technically quite different from McRae’s delicate, almost fugitive portrait, its everyday subject is treated in a way that makes the ordinary and familiar seem remarkable. What especially struck the judges was the successful achievement of such effects as the sheen on china and glass, and other details like the motionless fly. “The baked beans look almost edible,” said one. There’s also a touch of humour in the one-word headline on The Sun’s front page — TOXIC.

The prize for the best submission by a young artist goes to Self Portrait with Tower by Peter Haslam Fox, which only just qualifies for this special award since the artist was born in 1978 and might even have celebrated his 30th birthday by the time he receives his cheque. Still, in this large painting, he looks young enough, standing on the road at night in front of the Hilton on London’s Park Lane. You have to wonder what he can possibly see through those sunglasses because everything is so dark already. Indeed, the considerable visual impact of his watercolour derives from the strong contrasts between the black sky and the artificial lighting, not least the blue in which the tower is bathed. Interestingly, from 2006 to 2007 Haslam Fox studied under McRae at Southwark Art Academy.

The winner of the new award, the Penguin prize for cover art, was David Firmstone’s The Persistence of Memory; Dali-esque in title, if not in style. Clearly, the judging panel wasn’t entirely qualified to have the final say on the winner here; while we were looking for mastery of technique, strength of imagination and so forth, anyone creating a Penguin cover has to think of such matters as visual appeal, how well the image will reproduce and whatever else is usually expected from an illustration. So we needed to recruit a specialist to award this particular prize. She turned out to be Samantha Johnson, senior picture researcher at Penguin Classics, who silently sat among us taking notes while the pictures passed by. At the end, her mind fully made up, she strode purposefully towards Firmstone’s watercolour, declaring it to be ideal for its purpose. It’s atmospheric, even slightly menacing, she told us, and hints at a narrative that is all the more effective for never being spelt out.

RWS/Sunday Times Watercolour Exhibition, Bankside Gallery, 48 Hopton Street, London SE1; Sept 10-21, 11am-6pm daily, admission free. Sunday Times readers are invited to a private view of the exhibition on Sept 17, 6pm-8pm. Booking is essential: contact Parker Harris at rws@parkerharris.co.uk or call 01372 462190

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