Part-time Chicagoan Vicki Z. Peterson presents two older films (which she now shows only on video) and two new digital videos. In the most successful of these plotless visual studies, Sea Changes . . . An Evolving Series, the camera looks down from a great height on a stretch of ocean and shore. As waves move across the screen, they look like a finely textured rippling curtain; a familiar surface becomes a lush abstraction. The irregularly moving horizontal bands of color in Scrolls (1978) make patterns that are intriguing for a while, but at 20 minutes the film is too long. Rainbow Bridge (1975) applies single-framing technique to landscapes. Rapid intercutting of various perspectives—upside down, right-side up, obliquely angled—induce a sensation of orbital motion around an empty center. But because the movement is jittery and unstructured, this too becomes tedious. Also showing: Transforming Obsidian (Part 1) (2002). 90 min.