The emergence of Optical Art in the 1970s provided a breakthrough for Dumbrell, who credits Bridget Riley and Jesus Rafael Soto as early influences, and the nature and behaviour of human visual perception would prove fertile ground for the rest of the decade.  She began to use the grid as a foundation for her compositions and the subsequent works had a clear horizontal or vertical linear direction. Continuous stipes of complementary colours could produce the dizzifying hum of works like Stridor (1972) in the Queensland Art Gallery collection or Solstice (1974) in the Art Gallery of New South Wales collection. Cropped and apparently curving lines could produce the blooming movement of Foehn (1975) in the National Gallery of Australia collection. Carillon, 1971, employs vertical stripes of abutting blue and yellow, interrupted by sections of red and small squares of green—both of which seem to try and send the viewer’s gaze off-piste. The relatively sombre silver-grey ground, similar to the tones in Stridor, are opposed to the bright oranges and greens of the works that followed.  Dumbrell’s line eventually exploded into an array of fragments in colour space—likened pictorially to ‘pick up sticks’—which the artist saw as an extension of the spatial aspect of her work: where she had previously captured the searing heat of a hot summer solstice using colour and an intense optical illusion, she now played with the line in a freer, more intuitive way, floating in a landscape or skyscape.  Outside the studio, in 1975 she was a founding member of the Women’s Art Register, and was later involved in the influential feminist magazine Lip. From 1979-81 the Australian Tapestry Workshop commissioned two large adaptations of Dumbrell’s works and in 1982 she was commissioned to design the carpet for the lobby of the Prime Ministerial Suite of the new Parliament House.

At the turn of the decade the art market was booming, Dumbrell had exhibited work at Betty Cuningham Gallery in New York, had moved into a new warehouse studio in Richmond and the work took on a more freestyle. A calligraphic zigzag and a scribbled fan shape entered her works on paper, which then grew into a blockier lightning bolt and eventually developed into the “shape” paintings in which jagged, leaf-like forms interlock across the entire canvas—as in Akakia (1987). In 1986 Dumbrell, Robert Jacks and Victor Majzner were the subjects of a focussed exhibition of recent watercolours at the National Gallery of Victoria titled Colour and Transparency, curated by Patrick McCaughey. He wrote:

Ever since {Dumbrell} emerged as a distinctive artist in the late 1960’s, her work has had the impersonal exhilaration found in the best abstraction of recent years. Her rhyming compositions which began with strongly optical formats have moved steadily towards a freer, more open way of working. The rhyming elements are still there but the construction of the pieces has become more intricate, more dependent on moment to moment inspiration. The chief agent of that change was the transformation of her palette over the past three to four years. She had started out relatively austerely, working through tonal colour where balances of light and dark were as important as the interaction of hues, but recently the intensity of the hues—lustrous blues and purples together with sharp and rich warmer colours—have mattered increasingly to her. Under their impact, the formats had to loosen up.

Many of the “shape” paintings employ a translucent wash-like surface texture: as in Akakia (1987) some of the sections in Zavana (1987) in the National Gallery of Victoria collection are more opaque than others— and the connection to the watercolour medium is clear.  Dumbrell has maintained a practice of watercolour and gouache on paper throughout her entire career, producing stand-alone works such as Aqua (2010) as well as detailed studies for all her paintings such as Study for Colombe (2011).  This is the time and medium in which she “nuts out” the composition and colour plan for larger works—a process that can take weeks or months. All her line work is done entirely by hand—no tape is used—and (perhaps a surprise to some) she usually paints the line first before filling in the background colour; a laborious but meditative task. 

In 1990 Dumbrell moved to Bangkok where she continues to maintain a home and studio. Whilst a grid system and optical illusion returned to her work after this move, a sense of place in the work was heightened: the geometry of the sprawling high rise city, the tropical climate, and the colours and smells of a rich south-east Asian culture were naturally absorbed into the paintings. The decade culminated in a survey at the Ian Potter Museum of Art titled Shades of Light: Lesley Dumbrell 1971-1999, curated by Frances Lindsay and Rachel Kent, which included Veridian, 1999.  Kent wrote:

An exploration of natural forces—wind, rain, a bright summer haze, the setting sun—is coupled with a subtle evocation of intuitive or emotional states. Seasons, months, day and night are conveyed visually, and sometimes articulated in the titles of individual works.

In other words, it’s all about atmosphere.

In 2002 Dumbrell returned to Australia to begin building a home and studio near Euroa in the Strathbogie Ranges, where she continues to live and work during the warmer months of the year. Again, the vast panoramic view of rolling hills from her home and studio—together with the surrounding bushland—not surprisingly made its way into her paintings, though in this case the straight line of the grid was replaced with more random systems and an undulating line, more in tune with the natural world around her (Aurora, 2011 is a good example). Her evocation of and her absorption in her surroundings remains a central force: whilst she often titles her recent works using a book of colours, concerns of bushfire and flood can also lie in the background. A selection of works from this post-2000 period were selected for Lightworks, an exhibition at Australian National University’s Drill Hall Gallery in 2020, alongside works by Virginia Coventry, Trevor Vickers and Richard Dunn. 

Since 2015 Dumbrell has been thinking more three dimensionally, and plans to fabricate and exhibit a large-scale sculpture installation are underway. She’ll be included in Melbourne Now at the National Gallery of Victoria in March 2023, and her work is set to feature prominently at the Art Gallery of New South Wales in relation to the opening of their new building. 

Kate Nodrum, December 2022 (adapted from her catalogue essay for the exhibition Lesley Dumbrell: Atmosphere, Charles Nodrum Gallery, 17 September - 8 October, 2022)