Janice McNab seems to regard themes as a pre-modernist would have considered still-life painting—an opportunity to flex the paint, rehearse texture and understand the effects of light on forms. Over the years McNab has investigated such themes as aeroplane seats, dermatological reactions to toxic chemicals, and its effects on sufferers, and now volcanoes. By circling each area of interest through a number of paintings, McNab drums up sub-themes, analogies and allegorical significance like a bird raising worms—or a still-life painter exploring objects.

The insistent nature of working in series is instrumental in complicating a painted image beyond its immediate reception. In the mind of the viewer, image and meaning are generally linked by a path of least resistance, but an idea approached through a number of images creates a map with more lateral byways. Here the core theme of volcanos is tackled using photographs, detectable in McNab’s reiteration of the photojournalist’s classical sense of composition. Bright spurts of larva erupting in darkness and sclerotic blankets of smoke demonstrate extreme moods of nature, while a party on the ridge of an extinct volcano make humans look positively vulnerable in its presence. McNab has obviously been impressed by the sublime, but she does not translate this into incomparable landscape paintings. These are very much paintings about representation rather than attempts at it.

Two of the more painterly images here are not simply paintings of a photograph of a volcano, but of the pages on which the photograph is reproduced, including the dark straight valley up through the centre of the painting where the publication is bound and, towards the edge, sheens of reflection where atmospheric light or the camera flash has bleached out the printed image. These are not photorealist indulgences in illusion however, but duplicitous images that draw the eye first to one level of representation, then to another, and then again to the surface of the paint itself, with its obvious revision and underpainting.

McNab’s brushwork has relaxed noticeably in this show, as has her associative approach to themes. Where previously the paint would lie in complicit slicks and slabs, now it seems to work harder, as if the image were brought about through more of a struggle. It could be that this is McNab reflecting on her latest subject matter, introducing its tumult to the canvas and paper. Indeed the two paintings here that stray slightly from the central theme recall the control of previous work: the paint describing the hazy corollaries of a pair of car headlights in the dark and the striated delicacy of a glasshouse has been applied altogether differently. Although the press release attempts to homogenise the work, marking these last two pieces as contemplations on our vulnerability and the violence of our immediate environment, McNab evades thematic reductionism by continuing, like the still-life painter, to rehearse a painterly polyglot.

Sally O’Reilly is a London-based writer