Walking through the gallery, I murmur an apology as I bump into my own surprised reflection.

Until that moment, I thought I was strolling down a straight hallway with a window looking out into the serene gardens at the end. But a barrier of cold glass – a cleverly angled floor-to-ceiling mirror – shows we can’t rely on our eyes to know our surroundings.

“A lot of the time we walk around unaware,” the artist, Natasha Johns-Messenger, says. “That little bit of danger is not a bad thing. It’s just going to jolt you into not taking your immediate environment for granted.”

The Melbourne-born, New-York-based artist is in town for the launch of her new solo exhibition at Heide Museum of Modern Art, Sitelines. Mirrored installations are used throughout, appearing alongside light-works, photographs, film and live multimedia.

The site-specific exhibition is not only built into Heide’s very architecture, but reacts directly to the place. Johns-Messenger’s abstract photographs and film loops, shot here at Heide’s gallery and gardens, are often out of focus or microscopic in scale. It’s near impossible to place exactly what you’re looking at (hint: one is of the top of a parking bollard) – but piecing them all together creates an impression of a whole.

In one room there is a downward-sloping circular window. Outside you see the bare tree branches in Heide’s garden swaying in the wind. But the height is wrong. And the trees are upside down.

This is what Johns-Messenger calls a “real-time image capture”.

“It’s similar to a photograph, but it’s not – because it’s live,” she explains.

The real outdoor scene is framed and composed just like painting, or a film, or a photo, and “re-presented” by the artist for the viewer.

At first the mirror-trick window makes you feel physically unbalanced. But spend time there, staring, and you wonder how long it would take to become used to it. After all, our eyes already see the world “upside-down” anyway – it’s our brains that learn to flip the image.

Many parts of the exhibition are interactive. The mirrors aside, there’s also a video camera that can capture you and your friends inside a bubble that slowly drifts around a live projection of the outside garden.

Because her works play with reflection and light, she says often “the viewer becomes the subject matter”.

Johns-Messenger and I go inside a circular installation called Enfolder. The walls of the installation are lined with more mirrors. Johns-Messenger walks a few paces in front of me. As I try to keep up, I’m looking at the back of her head. And in my periphery, I see the back of my own head, looking into the back of hers, and so on into infinity.

As we lap Enfolder we discuss her interest in the stars and how what we see in the night sky is not reality. Because of the time it takes for the light from the stars to travel to earth, we’re actually seeing stars that may no longer exist. It’s an impression.

“You’re light travelling towards me, that’s how I’m seeing you,” Johns-Messenger says, her form echoed by an endless waterfall of reflections. “What if the whole thing is an illusion, and any person is an impression? What’s the distinction – the stars coming to me in the sky, or you coming to me here? So I created spaces where the viewers couldn’t quite tell who was real and who was not.”

Sitelines: Natasha Johns-Messenger is showing at Heide Museum of Modern Art until September 25.

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