Zurich- and London-based Raphael Hefti’s works at this gallery present an innovative approach to the artist’s practice, in which material experimentation, explorative processes and techniques, and the incorporation of non-traditional art production methods are combined in impressive sculptural and photographic works. Hefti appropriates specialised industrial processes and employs technical ‘tests’ to push the limitations of utilitarian materials, often drawing on the failings of certain processes or materials and exploring the errors created by misusing them. His works are primarily concerned with the properties of materials, as well as how these qualities operate with the spaces around them. Thorough research periods are reflected in these investigations into specific processes.

Polish artist Agnieszka Polska also references the convergence of science and artistic practice, as well as the lives of objects and materials, in simple yet hypnotically alluring video works. In this exhibition, each presents an interpretation of reality in various forms, often with low-tech or strangely uncanny elements, and often with a focus on memory, history and the passage of time. Art-historical references, and ‘disappeared’ artists and artworks, are also motivations in her work.

The exhibition opens with Hefti’s Various threaded poles of determinate length potentially altering their determinacy (all works 2014), a forest-like installation of floor-to-ceiling metal poles, each treated with various industrial chemicals or processes that leave the metal marked with various colours and finishes, or scorched and eroded. The poles delineate the room into a dynamic, shifting grid of brightly hued metal, functioning as a large-scale, graphic form and individual, nuanced formal elements. There is a visual frailty to the poles that somehow diminishes their impact as irrevocably concrete objects – they seem to act as lines in a drawing or blueprint more than actual metal – an uncertainty that is erased in the subsequent, resoundingly physical works.

The viewer is next presented with Polska’s new work I am the Mouth II, an incredible, bizarre, hallucinatory vision of a disembodied pair of lips semi-submerged in rippling blue water, calmly and slowly whispering sentiments about itself. The mouth is intended to function as the ‘voice of an art work’. The work is disturbingly sensual, almost erotic, in a dreamy, otherworldly way. Technically, the video’s effects seem intentionally dated or cheaply executed − the water looks like poor quality CGI and the mouthed words are slightly out of synch with the audio − emphasizing the pseudo-scientific approach taken towards reality in her works. Polska is interested in the perceptual phenomenon ASMR (Autonomous Sensory Meridian Response), in which the viewer experiences a pleasurable tingling sensation in the scalp, head, back or other regions of the body in response to certain visual or auditory stimuli. Whispering is thought to be a common trigger for the phenomenon.

The second room is dominated by nine immense Hefti photograms, printed on entire rolls of photographic paper installed at the ceiling. The massive, stunning works are created by dusting the paper with ‘witch powder’, or lycopodium,  a type of moss spore that illuminates when ignited and exposes the photosensitive material. The result of this process manages to simultaneously resemble red seas, polished pink marble, magnified skin and monochromatic impressions of pyrotechnics, each falling in a grey area between abstracted image and objective form. Palpably material in their essence, the photograms seem to exist as pure, monolithic object, as sculpture more than photograph, in an interesting twist on the representational nature of the medium.

Easily overlooked in the same gallery are three small, etched ‘totems’ by Hefti: slabs of copper, zinc and aluminium mounted on poles installed floor-to-ceiling. These seem deeply rooted in explorations of the qualities of their respective material and don’t seem to suggest much beyond it. Perhaps they would offer more if they were not overwhelmed by the bombast of the massive photograms behind them.

Onwards, three of Polska’s videos loosely montage references to Polish cultural history with appropriated documentary footage. The Garden references Paweł Freisler, a Polish artist who abandoned his practice in the late 1970s to become a gardener – this interest in ‘disappearing’ artists recurs in other works. The quiet rumination on the science of plant life is lovely – studied, calm and vaguely mysterious. The digital animation Watery Rhymes is an investigation into the physics of language and how various materials affect sound waves. How the work is done borrows documentary elements from the 1956 Krakow Academy of Fine Arts student strike, in which students protested Communist labour standards, and Polska applies the concept of hard labour to the artist’s practice and the production of artworks. Each video deftly handles complicated information and layered cultural/historical references while retaining Polska’s identifiable hypnotic, calm aura.

The final installation of Hefti’s works is Subtraction as Addition, three large-scale glass panels treated with multiple layers of anti-glare coating, often used in the conservation of artworks. Each panel is treated with different amounts of the coating, which then begins to gently bubble and buckle, distorting the flat glass into subtle waves of iridescent reflections that recall oil stains or smoked mirrors. With each sheet of coating applied, the glass darkens – one piece is nearly black. By building layer-upon-layer of this protective material, intended to be unnoticeable, Hefti cleverly reverses the material’s original function and gestures towards the conventions of viewing and the materiality of the object. Additionally, by transforming clear glass into mirrors, the viewer is made acutely aware of their own presence in the reading of the artwork.

Lastly, Polska’s complex and haunting video Future Days presents the concept of the legend through an imagined afterlife in which dead artists from different eras meet. The artists featured − Paul Thek, Jerzy Ludwiski, Włodzimierz Borowski, Lee Lozano, Charlotte Posenenske, Andrzej Szewczyk and Bas Jan Ader − are notable for their sudden disappearance from the art world (particularly Ader, who was lost at sea in 1975). Filmed in Gotland, the setting is stark, minimal and still. The artists (actors wearing unconvincing, rudimentary masks) traverse the isolated barrens and engage with ruins of lost artworks – Robert Smithson’s Partially Buried Woodshed makes an appearance as a temporary shelter for the troupe. Questions of existence and temporality are raised with little provided in the way of answers. Laden with art-historical references, the work is evasive, confusing and oddly compelling.