The horizon, as glimpsed from his Southampton home, is an ephemeral demarcation of ocean blue blending hazily into the infinite canopy of sun-dappled space. Roy Lichtenstein sought to define that boundary between terrestrial and universal. In his visual quest, the late artist best known for comic-strip imagery is credited by some art scholars with reinventing American landscape painting.

"Roy Lichtenstein: Between Sea and Sky," the new Guild Hall exhibition, explores that career-long quest. Though he's a cornerstone figure in the 1960s pop art movement -- along with Andy Warhol, Jasper Johns and James Rosenquist -- Lichtenstein returned repeatedly to land- and seascapes until his death at 73 in 1997.

"We want to draw attention to a major part of his work that many people may not be familiar with," says curator Christina Mossaides Strassfield, "and to show the range of his ingenuity."

POP-SCAPES In this exhibit, you see Lichtenstein's fingerprint everywhere -- just not in the context we're accustomed to seeing. Not the Roy Lichtenstein of soap-opera comic-strip "Drowning Girl" (1963) or air-battle "Whaam!" derived from DC Comics' "All-American Men at War" (1962). His posthumous notoriety peaked with the 2013 sale of "Woman With Flowered Hat," a Picasso homage, for $56.1 million.

Lichtenstein deployed his pop techniques in creating landscapes as early as 1964 with "Sea Shore," oil and Magna (early acrylic paint) on Plexiglas. Sky, clouds and ocean are rendered in varying shades of Benday dots, then ubiquitous in newspaper reproduction, accented by yellow brush strokes to indicate sunrise. His art reflected mass-media influences in a less cynical way than, say, TV's "Mad Men." His landscapes are grounded by natural-world inspirations, many observed from his Southampton estate where he moved with his wife, Joan, in 1970.

PLASTIC FANTASTIC With 31 works, Guild Hall's show makes an admirable if vain attempt to encompass the exploratory range of Lichtenstein's landscape curiosity. Among his experimental materials was Rowlux -- "plastics" in the vernacular of the whispered advice to Dustin Hoffman in "The Graduate." Lichtenstein applied the undulating material to mimic shifting qualities of sand, sea and sky. In three pieces on display, the artist added a motorized element to capture changing atmospheric light and the rocking of waves, also captured in the only film Lichtenstein created -- side-by-side looped reels of Montauk waters beneath a Benday sky and a stationary gull perched over a rocking seascape. Meanwhile, you can't miss the 18-by-29-foot "Super Sunset Boulevard," a reproduced artifact of a failed project to mount high art on billboards across America.

"His work was part of the zeitgeist of the time," says Clare Bell, essayist for the exhibition catalog. "We see them as landscapes, but they're really abstracts in Roy Lichtenstein's unique style."

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One such image, "Night Seascape" (1966, on felt) is available in the gift shop as a beach towel. Just $300.

WHEN | WHERE Through Oct. 12, Guild Hall Museum, 158 Main St., East Hampton. Hours: noon-5 p.m. daily through Labor Day, 11 a.m.-5 p.m. Mondays, Fridays and Saturdays, noon-5 p.m. Sundays thereafter

ADMISSION Free; 631-324-0806,