Reviewed:

Taint, John Cronin, Green on Red Gallery, Dublin, until October 5th (01-6713414)

Metastasis, Sharon O'Malley, Hallward Gallery, Dublin, until September 20th (01-6621482)

Aine Nic Giolla Coda & Eamon O'Kane, Fenderesky Gallery, Belfast, until September 27th (048-90235245)

Arran Henderson & Marianne Potterton, RHA Ashford Gallery, Dublin, until September 20th (01-6617286)

Bob Lynn, Solomon Gallery, Dublin, until September 19th (01-6794237)

John Cronin slides sharp, high-octane colours around in a manner pioneered by Gerhard Richter and since widely practised. Both Richter and Sigmar Polke look like influential exemplars for Cronin. Lately, he has diminished the friction of the process by working on sheets of aluminium rather than wood panels or canvas, providing fast, slick surfaces.

The ambiguous title of Taint, his show at the Green on Red Gallery in Dublin, could refer to the way a given, fixed image is smeared and distorted or to the introduction of rogue elements in terms of colour or surface markings.

A connection is made, in an accompanying explanatory note, with the way computer disks can become corrupted, so we can read the title as a metaphor, one perhaps referring to many such processes.

Visually, the smeared images, though abstract as far as one can tell, resemble photographic effects such as distorted video signals. The work's appeal depends very much on the generation of surface excitement, and that, in turn, is largely dependent on one effect.

Even a mild variation of this, in the form of the curvilinear patterning of No 19, doesn't work out well. As a result, there is a certain thinness to the show.

Cronin comes up with some good colour combinations, but overall he is an unsteady colourist. There is a fruitful complexity to No 4, which, though it is uneven, sees the artist getting into some difficult areas and trying to paint his way out of them, but often you get the feeling that he is not really pushing himself.

About 40 per cent of the work (including Nos 4, 6, 10, 11, 14, 15, 21 and 22) is pretty much spot on and convincing, which is probably, come to think of it, a pretty good average.

Sharon O'Malley's paintings in Metastasis, at the Hallward in Dublin, draw on classical mythology and, not uniquely, use the device of a distressed, textured surface to suggest antiquity. Her choice of a term more commonly employed in a pathological context for the show's title is puzzling.

While her work deals with the continuing resonance and relevance of myth, there is no indication that that's a bad thing, so presumably she means it in a more general sense of transformation.

Her paintings feature heroic, classical heads, usually in profile, and full-length figures, generally depicted in a more passive, sensual way, as in the mysterious Elevation, in which the prone figure seems to be perched atop twin pillars.

Everything is filtered through accumulated layers of glazes and textures, creating a sense of great age, something augmented by the sepia tones that describe the figures. The work projects feelings of endurance, of weathering, of the maintenance of a classical calm and poise through the flux of events.

Arran Henderson and Marianne Potterton complement each other neatly in a fine photographic show at the Ashford Gallery. Both prowl the shoreline, responding to natural processes in different ways.

Potterton also works in other contexts, but wherever she is, her method is to set up situations, visual experiments, such as her sumptuous Ice Melting On Indigo images, and record the results.

This can recall aspects of environmental art, and begs the question of whether the work is contained in the action, with the image as documentation (which would be absolutely fine, and is a notion supported by the inclusion of a video piece), but the aesthetic qualities of her images tend to suggest otherwise.

For the most part less interventionist in his approach, Henderson has produced some extremely striking images. Some of them, as he notes, are striking because he framed compositions "that seemed to resemble paintings", while others, "recordings of recordings", light on tiny events that are beautifully transcribed, including the patterns scored in sand by a tangle of snagged twine or a feather. These are delicate, gentle works that are also surprisingly rich in terms of appearance and ideas.

The prolific Eamon O'Kane is showing photographs at the Fenderesky Gallery, in a two-person show with Aine Nic Giolla Coda, who shows photographs and drawings on glass. O'Kane's large-scale "computer manipulated" prints come across as on-the-road snapshots, anecdotal and miscellaneous glimpses of things seen in passing. They are agreeable and well composed, though also curiously impassive, perhaps by design.

Nic Giolla Coda continues her exploration of architectural spaces with a series of Cibachrome studies of the interior of an unnamed Georgian town house. The restored interior, with its sanded wooden floors, looks unoccupied (though there is a grand piano in one room), and the images are hard lit and contrastive, so the house looks handsome but unsympathetic and uninviting.

The drawings strip aspects of the photographs down to spare linear statements of architectural (and some incidental) detail. They are intriguing pieces of work, spatially strange because of the transparency of the glass allied to their unmistakably architectonic nature, and, presumably intentionally, they benefit from their setting in the Fenderesky, which echoes the depicted space in several respects.

Bob Lynn, at the Solomon Gallery, is a Scottish-born, Wicklow-resident painter who has moved towards abstraction from conventional representation, but he mostly abstracts from his favoured subject matter, landscape. He also cites weathered surfaces as sources in his recent work, which is intended to evoke, as he puts it, "a sense of" rather than provide a direct depiction.

A bold colourist, his most successful pieces are marked by a strong sense of structure and pattern, rather in the manner of Nicolas de Stael. Outpost and Quiet Haven - a carborundum print - for example, have strong cruciform structures, while Beyond Compare sees him convincingly explore a paler, quieter tonal range.