Slow Hope by Mandy Martin and Alexander Boynes is part of a mother and son collaboration that, in its present incarnation, has been going on for about six years. The unifying theme is climate change and there have been four major exhibitions. The most recent is the Hi-Vis Futures show presently on display at the Canberra Museum and Gallery.

The exhibition, Slow Hope, takes its title from the influential essay by Christof Mauch, Slow Hope: Rethinking Ecologies of Crisis and Fear (2019) where the author builds on Rob Nixon's concept of slow violence - a tale of gradual environmental degradation - to relate the idea of quiet but positive environmental change.

Mauch uses the aphorism attributed to the British philosopher John Stuart Mill: "Every great movement must experience three stages: ridicule, discussion, adoption." He argues just as "slow food" has in some places replaced "fast food'" now there exist many positive environmental developments by individuals across the globe that can give rise to slow hope.

If the Hi-Vis Futures show has almost a hysterical element warning us that the environmental apocalypse has already commenced and that we have to fight the use of fossil fuels now, Slow Hope presents an olive branch of hope for an alternative future.

Martin, who has had an obsession with smokestacks for at least a couple of decades, juxtaposes the satanic mills in the background with images of green growth and fecundity in the foreground.

In her major painting Knowns, the tropical forest dominates the foreground space with its rich array of greens, browns, ferns and fronds, while the power station in the background appears anachronistic and a relic of the past. I am reminded of the great European romantic tradition in the depiction of ruins, where monuments from past, vanquished civilisations have surrendered to a slow decay and their earlier pompous declarations now seem silly and hollow.

Martin draws this parallel with the present-day champions of the coal industry as being on the wrong side of history with their destructive empire now crumbling. Nature will grow over the scars and the wounds that they have left on the living earth. She works with pigments, acrylic and oil to frequently create a gritty, tactile and organic surface.

After exhibiting for more than four decades, she displays a mastery of touch that is both intuitive and beautifully descriptive.

Boynes has been experimenting for a number of years with new technologies and in recent years has been increasingly working on aluminium composite panels. The work in this exhibition is his strongest to date and he has opted for a much more subdued, at times almost monochromatic palette.

There is a great difference between an image that is "snapped" and an image that is "drawn". Much of his earlier work was reliant on a photographic source - which is very appropriate for some sorts of art.

Here much of his mark making is drawn and betrays more of the human touch with the image increasingly humanised.

A break in the clouds, one of his strongest pieces at this exhibition, is quite a subtle play of time and texture as his mixture of ink and enamel slides its way across the slippery surface of the metal.

Here the eucalypts of hope in the foreground contrast with the smokestack cooling towers in the distance.

There is hope that slowly the tide will change and that humankind will triumph over the disaster that presently afflicts us and threatens our very existence.