Canvas v camera

Britain's two most famous living painters - Lucian Freud and David Hockney - are very different in their brushes with publicity. Freud maintains complete silence, while Hockney opts for noisiness. Frequently in print or on television with some gee-whiz theory about how past painters worked, he has now declared war on photographers of war.

For a New York exhibition, Hockney has made a watercolour - reproduced on the cover of this week's TLS - based on Picasso's painting Massacre in Korea. He has called it Problems of Depiction and added a note which suggests that both the Picasso and this new spin on it are "a painter's response to the limitations of photography, limitations that are still with us, and need some debate today".

Perhaps because he possesses a painter's typical nervousness with words, Hockney omits to spell out these limitations, presumably inviting us to deduce them from the image. So let's employ our eyes' equivalent of the camera's zoom and consider what we see.

Picasso's Massacre in Korea is a 1951 oil painting which was spurned at the time as a mere minor skirmish after Guernica. On the left side of the image stand four women, one pregnant, and probably (Picasso's scatter-shot anatomy instilling doubt) four children. All naked, they huddle together, apart from one baby picking flowers. Facing them are five soldiers aiming weapons at them through a classic Picassian patchwork of eyes and armour. On a hill in the background, a ruined building burns.

Fifty-two years later, Hockney's watercolour reply consists of two images, the topmost more or less reproducing the Picasso although the bodies are a vivid pink against the grey of the original. This may reflect different palettes or, perhaps, a desire to stress that these victims are full of blood. Hockney also paints more children, partly to obscure the genitals of the mothers, which the Spaniard enthusiastically brushed in. We may take from this change that one of Hockney's concerns about war photography is prurience and the risk of liberal porn.

The military side of the picture has been altered more: Hockney's troops have guns which resemble microphones (or "mike-guns", as they are sometimes known in TV) and are also holding a piece of equipment (rectangular with spools) which looks rather like a video-camera. Hockney seems to be making a connection between soldiers and photographers, the rifle and the camera. His implication is that Picasso was saying the same.

This suspicion is increased by the lower image, which has no equivalent in the original: a rear view of the chubby grey-flannelled legs of a photographer beneath the kind of cover-sheet used by old-fashioned snappers. We're surely supposed to conclude that the blanket prevents him from seeing straight. Send the paintbrush to the frontlines, Hockney appears to be saying, not the Nikon or the Sony.

The explanatory note expands on his objection to paint's hi-tech rival. Massacre in Korea, he surmises, was inspired by photos from the Nazi death camps. He goes on: "Picasso realised that the photographs were after the event, indeed in a way not telling us of the terrible brutal activity of the camps but of the survivors."

Hockney tends towards an impasto prose but seems to be saying that the camera can only capture what it is allowed to see. The death camps excluded cameras, so the only record is of survivors, a potentially false optimism. Perhaps, but when the death camps were liberated, photographers captured horrifying images of heaped corpses. It's certainly true that painters can create images of scenes they never saw but that's a dubious superiority because imagined images have the same problem with historical authority as, in an age of digital manipulation, a photograph now suffers.

His stronger argument is that photography is physically invasive in a way that painting isn't. The huddled, naked victims of war are being violated for a second time by tripods and mike-guns. This is a fair point, especially as we can now see that Picasso used the discretion device of pixelation long before TV discovered it.

Hockney's problem, though, is that a painting - especially an abstract one - can mean anything the viewer wishes it to. Without its title and footnote, Problems of Depiction could be taken as a standard attack on the military. The camera may lie but abstract painting is an institutionalised fib.