Exposed to a process of unpainting where risk of failure is essential

VISUAL ART:TURNER, OFTEN described as the greatest of all British artists, was once criticised for "painting pictures of nothing, or very like". Contemporary Scottish painter Callum Innes goes one further.

He initially became well known for his Exposed Paintings, in which blocks of colour were systemically dissolved by the application of turpentine. Each finished work consists of an area of primed, unpainted canvas, an area of painted colour, often black infused with other hues and, adjacent to this chromatic block, the residue of colour that has been washed away.

Sometimes this residue is nothing more than a pale, virtually colourless tone, but on occasion it is a lush burst of colour, startlingly revealed when the overlay of black has been stripped away. We see a painting that has been made and unmade, and in the flow of the turpentine, get a sense of a process fixed in time.

While it might seem as if Innes was deconstructing painting, or deconstructing minimalism, and what he does has been termed "unpainting", it is also true that in most cases the painting process in general consists of a combination of making and unmaking. His work not only alludes to this but translates it into a means of approach and a visual form. It is as if he continually questions the basis of every stage of his own methodology. Each step and movement is analysed and considered and made to yield some usable detail.

The end result is, he intends, that we should be able to look at any one of his paintings and find enough clues to decipher the logic of its constitution. What might seem impassive and ungiving turns out, on reflection, to be surprisingly engaging and negotiable.

His current show at the Kerlin Gallery features several Exposed Paintings, what might be terms Innes classics, but it is actually exceptional in the sheer range of work it includes, from fine examples of his Monologue paintings to several intensely coloured Exposed pieces (red, yellow and blue) and a sequence of quite large Cento works on what he knows colloquially as "butcher's paper", that is, waxed paper.

The result is an unexpectedly rich, varied and vibrant installation from an artist whose exhibitions can often seem austere at first glance, partly because of his liking for monochromatic colour schemes, and partly because he works in series, and a show is likely to feature examples drawn from a single series and therefore of a certain uniformity.

The diversity of the work in the Kerlin, he says, has much to do with the fact that for some time now he's been working in a much larger studio, something that seems to be beneficial in more than a purely logistical way.

Incidentally, while he works in series, they are not chronologically contained, and it is clear that he likes recurrently to bring new thoughts to each of them. The way of working encapsulated in the Cento pieces, for example, extends back to some of his earliest works.

His most recent solo show, at the Frith Street Gallery in London, consisted of a set of large-scale Monologue paintings. Another of these features in the Kerlin, and at 2.2sq m, it is the largest work in the show. The Monologues differ from the Exposed works in that the space in them is not divided up. The entire surface is painted and then variously dissolved with turpentine, generating washes and curtains of tone that have an organic, almost landscape feeling.

Other potential references also come easily to mind, and Innes seems content to let any and all potential readings be. He's altogether comfortable with the words landscape and figuration being used in relation to the horizontal and vertical emphases in paintings that many observers would describe as purely abstract.

It's worth pointing out that he began as an explicitly figurative painter who shifted over to abstraction, not because he was rejecting figuration, but as a way of developing his own language. The physicality of the work, the way people respond to and interact with the paintings, the idea of leaving space for them to do so - all of these things became more important.

He notes that when he began to use intense blacks rather than greys in the Monologues, they became "more figurative", in the sense that they became more visually complex and ambiguous, so that "you can read what you like into them".

His use of the word "exposed" immediately brings photography to mind and, as it happens, the photographic grammar of focus, exposure, positive and negative is most obviously relevant to the Monologues.

These works resemble black-and-white photographic negatives, not least in the way they look like images, but images inverted and abstracted so that they don't quite make sense.

There's also another striking quality, and that is the way in which the works are suffused with light. Innes notes in passing that he is sometimes taken aback when people talk about the blackness and darkness of his paintings. Alternatively, for him, they're all about light - the light that comes through.

This has to do with where the pictorial space is located. A recurrent format, one that features in the Kerlin, consists of a single, wavy vertical line etched into a long sheet of paper. It inevitably recalls the American artist Barnett Newman's celebrated "zip" abstracts, in which a vertical line bisects expanses of flat colour.

But for Innes there are significant differences, the most important of which is the attitude to space expressed in the works.

Newman, he says, is "in front of a space, declaring a space", whereas his line eats into the space. So rather than, say, imposing a black on a surface, the black is about the light behind the surface, and different paintings allow us different ways into it.

Innes is an artist who instinctively discards anything extraneous, and continually interrogates the elements of his formal vocabulary. His working method has a built-in risk of failure, entailing as it does "controlled chaos". But the risk of failure is essential.

There is, he says, "a sense of fragility about the work" that is important to him. At various stages, he notes, he's felt that the work might become mannered because he knew how to do certain things too well. "If that happens, it dies."

Hence his practice of editing his works a great deal and even, on occasion, destroying pieces that initially had seemed okay. "But," he observes, "the work is only really finished when it leaves the studio and when the viewer spends time with it".

Take the chance to do so.

Callum Innes, Paintings. Kerlin Gallery, 3 Anne's Lane, South Anne Street, until June 28