Viewed in reproduction, the early paintings of Jo Baer can make a misleading first impression. They might appear impassive, even “noncommittal,” to repeat a term used by John Ashbery when he reviewed Baer’s first solo show in 1966. Seen in person at Dia Center for the Arts’s current exhibition of Baer’s “Minimalist Years,” however, those paintings seem quite the opposite. They are grand, open, elegant things, and while these luminescent canvases are often pleasing to the eye, they are just as often satisfying to the intellect.

Dia showcases some of Baer’s most splendid efforts from the ’60s and ’70s, many of which address the instability of painting as a medium. Framing broad white rectangles of paint with dark bars of black outlines, for example, many of Baer’s seemingly blank tableaux enact the simultaneous acknowledgment and denial of the canvas (or any support) common to the normative appreciation of painting. In other words, with coats of white paint both referencing and covering the canvas proper, these works picture the (repressed) memory of the canvas that always haunts the medium.

Other canvases explore even more blatantly physical properties of painting. Like her contemporaries Frank Stella and Donald Judd, Baer tested the distinction between painting as an object in the world and painting as a purely flat optical field. Crucial to Baer’s unique exploration of this distinction was a rigorous investigation of the frame and the stretcher. Her wraparound paintings of the late ’60s and early ’70s are known best for this investigation, wherein black bars (punctuated with thin stripes of color) creep around the sides of the works to appear on the z-axis of the stretcher, as well as on the x- and y-axes of the front.

Baer wasn’t the first to allow paint to make such a peripheral appearance, but her investigation exceeded by far the more haphazard marginalia of other painters of her generation. Walk up to just about any of Morris Louis’s “Unfurled” paintings from the ’60s and you’ll be able to follow rivulets of paint up the canvas-covered stretcher bar. That paint, however, had been poured to the edges of the canvas before it was stretched, and viewers reared on modernist discourses were supposed to consider those marginal colors inconsequential, if not accidental. Indeed, discourses of “opticality,” as developed by critic Clement Greenberg and his tributaries, demanded that such paintings be considered pure visual fields—otherwise they were in danger of stumbling into the three dimensions of sculpture. So the paint on the sides of many “optical” paintings was a sort of open secret. One often saw, but was asked not to acknowledge, the colors on the sides, because the true painting was to stop at the edges of the pictorial plane. It was in this context that Baer’s work confronted the instability of the frame. Her black bars (even as they helped to “picture” the whiteness of the canvas) called attention to the frame’s dual function as a pure cut between work and world, and as a bulkier thing that does the more muscular job of supporting the canvas.

Curator Lynne Cooke opens the exhibition with a room of works that, though predating the wraparound paintings, develop similarly clever approaches to the image/support dichotomy. A couple of large paintings from 1962 and 1963 that are based on graph-paper drawings, for example, are concerned with the support of drawing (rather than painting), although “based on” might be putting it too loosely. These are, in fact, exact renditions, reproducing both the geometric figures of the drawings exhibited nearby and the graph paper on which those drawings appear—down to the slightly yellowed modulations on the paper. For the “support” of her drawings, Baer chose a green-lined graph paper that was punctuated with three groups of blue lines, like penmanship paper. On one sheet Baer drew a rectangle, the sides of which are two squares thick, over the grid. She then drew short black lines across the width of the long sides of the rectangle. It’s on those sides, with quiet precision, that Baer let the drawing converse with the graph paper support. The blue lines pass through the center of the rectangle with no effect. But in the lower portion of the rectangle, the blue lines seem to erase the short black ones. And in the upper region, the short black segments are further erased on either side of each of the blue lines. The composition of the drawing, in other words, yields to the interruptions of the blue lines on the paper. The subsequent painting is a portrait of that specific confrontation between support and drawn image.

Moving to the third gallery is like advancing to calculus after having taken a year of algebra, as some of the graphs and bars give way to softer curves in Baer’s so-called “orchid” paintings. Titled after plants Baer collects, the curving pastel motifs of these works seem to cling to and turn around the corners of canvases like the specimens for which they were named, prompting viewers to think of the image/support relationship as something like that of a parasite to its host. In the process, these paintings perform a sort of deconstructive violence on the very genre of “flower painting.” It is as if Baer took O’Keeffe’s pretty flower pictures and put them in a centrifuge, dispersing their forms out to the margins. Of course, there is a lot in these paintings for those who prefer not to crossbreed their abstraction with representation. The placement of some canvases horizontally and low on the wall encourages visitors to move up to and around them, thus allowing individuals to compare viewing habits common to sculpture (in which the viewer is often mobile) and painting (in which the viewer tends to remain in place).

It’s been several years since Baer’s early work received such careful attention in the United States. Indeed, given the dearth of scholarship on Baer, her work has been in danger of becoming as marginal as her signature motifs. The skillfully installed show at Dia, however, should help place Baer’s work (and keep it) front and center.

“Jo Baer: The Minimalist Years, 1960–1975” is on view through June 15.

Sarah K. Rich is assistant professor of art history at Pennsylvania State University.