This spring term, the Art Department will offer Colby's first semester-long course in fine art photography. Art198, Photography I: An Introduction to Basic Concepts, Techniques and Materials of Photography is the first level in what art faculty expect to expand into a fully rounded component of the studio art curriculum.     An advanced course will be introduced next fall, and over time students will be able to take a number of courses in photography, says Michael Marlais, Art Department chair.     "We've been thinking about this for years; it's something our students have wanted for quite a while," Marlais said. "At our senior exit interviews students often say they wish we had photography."     Deborah Randall, a first-year assistant professor of art, will teach the photography courses. "An art department could expand several ways and photography seemed like a natural for us because the interest already is there [among students]," she said.     There is no dedicated space for the program yet, Marlais says, so students temporarily will share rooms used by the Photography Club in Roberts Union and two darkrooms that will be renovated in Bixler.