An artist works in a series to explore a set of related ideas. Like a miner picking at a vein of ore, the painter establishes a point of view toward some internal or external reality, and then proceeds to give form to it in a group of paintings linked in content, style and attitude. A Monet painting of Rouen Cathedral becomes more profound when seen as one of a series. The French Impressionist interpretation of light, defined by color, dazzles in the single painting, but when seen as part of an investigation, the single painting becomes a point well made in a scintillating, continuing dialogue. We bear witness to the artist''s sustained examination of light and color, and are forever changed in how we see such things.

The new exhibition of paintings by Aromas artist Barry Masteller at the Trajan Gallery in Carmel affords the opportunity to see segments of three different series that reflect the artist''s concern for images that explore the misty world of memory and how the external world dissipates into potent dreamscapes after the mind and heart have edited out nonessential details.

In addition to his ongoing "Earth and Sky" series (Masteller has painted almost 500 of them), the Trajan Gallery presents the new "Boulevard" and "Soliloquy" series.

The "Earth and Sky" series offer iconic, if not generic, trees situated around coastal meadows drenched with the golden glow of evening. Red halos pulsate around the edges of the foliage and meadow grass like humid mists; all forms dissolve in the poetry of twilight. The theme and variations Masteller created in "Earth and Sky" amounts to a personal pastoral wherein a simplified nature is the vehicle for his experimentation; he has reduced nature to the form of horizontal of land, the vertical mass of trees, and the evocative event of fading light.

"I don''t consider myself a landscape painter, but an abstract painter," says Masteller. "I feel a kinship with Philip Guston and Joan Mitchell."

As Masteller paints an "Earth and Sky" painting, a general idea governs the process, but during painting he improvises, moving tree forms here and there, widening a meadow, redirecting a waterway. He then works the surface to achieve his desired effects. A close look at the surfaces reveals a restless brush, scratching and scumbling. But for all the lively surface activity, the works are controlled studies of the one idea: a disappearing sun dissolves form, dissolving forms are ripe with the poetry of memory and longing.

Like Monet revisiting the facade of Rouen Cathedral, Masteller returns repeatedly to an imaginary urban scene to, again, explore a theme and variations. The "Boulevard" series is full of the afterglow image of a nighttime city, the flash of lights, silhouettes of cars and people, window light playing on the pavement. People remain anonymous, even ephemeral, as they, mere faceless shapes, sit in bars and restaurants or cross the street.

"The last time I was in New York, I took my camera. I told myself, ''I''m going to photograph!'' I was way up in my hotel room shooting at the streets below. I really responded to the geometry of the crosswalks, the vertigo of the angles, the rounded curves at the corners."

With high vantage points, the paintings of the "Boulevard" series are dizzying views of streets defined by linear perspective. The interplay of flat, frontal forms and those locked into the perspective system is gentle on the mind; these are more like Hopper than Thiebault. As is his practice, Masteller edits out extraneous detail to create his urban scenes with a repertoire of elements: the pedestrians, the crowd silhouetted in the windows, the traffic lights, the crosswalk lines, the open doors with light gushing out, the glow of headlights and all the shadows cast from the lighted windows, the open garage doors or some mysterious, electric urban mist emanating from the high horizon. His boulevards, like the landscapes, are quiet and even contemplative, a Miles Davis ballad rather than a John Coltrane extrapolation.

Lastly, the "Soliloquy" series attempts to bring a human element to the landscapes. Masteller has introduced a predella to the landscape, a sequence of figures in their own separate painted partitions at the bottom of the canvas. These gaze into the distance; as we look over their shoulders, there is a tacit invitation for us to do the same.

"The ''Soliloquy'' refers to my relationship with the painting, the feeling of the painting," says Masteller. "What I really like is when people come up to me and tell me what the painting means to them. They have their own elaborate stories they fix to what I''ve painted. Frequently, it has nothing to do with what I was thinking, but that''s the way it should be. They get out of it what they want, or need."

Barry Masteller''s exhibition continues at the Trajan Gallery through Aug. 31.