This hauntingly beautiful exhibition was commissioned by the O3 Gallery at Oxford Castle. The artist, Mary Foulkes, modestly describes herself as “not a trained photographer and relying heavily on trial and error”. Yet she has produced a wonderful body of work about Oxford with a particular focus on the Castle complex and its environs and an exploration of Oxford’s waterways.

What makes her captivating images even more remarkable is the methodology and equipment she uses: pin-hole photography and cameras. Two of her cameras are shown. One, for simpler images, is an aluminium take-away container attached to a Polaroid photographic plate. The other, for more complex pictures, is an octagonal Quality Street tin with a pin-hole on each facet of the tin. Foulkes wraps her film around a wooden disc in the centre of the tin, an effect that produces dreamy over-lapping images. She will leave the camera ‘on location’ for anything from ten minutes to three hours.

Foulkes uses the pin-hole approach and the length of exposure to endow ethereal magical properties to her subject matter, giving each a new perspective via luminescence and the inter-play of dark with light.

In River Cherwell Parson’s Pleasure 1st May 2011 5.30 (above) the river expands magically to fill the picture with silhouetted trees seemingly retreating into the distance. And in Castle Mound, Oxford Castle 16th July 2011 21.16 there is a wonderful panorama of dark and light velvety blues in which are gently caught the lights of the surrounding area — Nuffield tower half seen and a quiet bed of light that gives New Road an unexpected romance.

Until November 13. Weekdays: noon to 5pm. Weekends: 11am to 4pm.