ROCHESTER, N.Y. (AP) _ Eastman Kodak Co. on Thursday unveiled an electronic film-editing system that marks the company's entry into the emerging field of hybrid electronic photography.

The Premier image enhancement system uses electronics to take the place of a razor blade or airbrush in manipulating a film image. It can be used for retouching, cropping, creating composite images, or changing the color, balance and contrast of a photograph.

''Electronics is going to take over the manipulation and storage of images in many ways,'' said Raymond H. DeMoulin, head of Kodak's professional photography division.

Kodak's experience in traditional photography gives the company an edge in hybrid technology, said Eugene Glazer, an analyst with Dean Witter Reynolds Inc.

Hybrid systems such as Premier have the potential to improve the quality of photographic prints, which could increase sales of conventional film products that are Kodak's mainstay, Glazer said.

Premier, introduced at the Photo Marketing Association International convention in Las Vegas, is faster and produces higher quality images than systems already on the market, DeMoulin said.

The system is made up of a film reader and film writer, identical gray boxes the size of a large chest of drawers, and a computer workstation based on a modified Sun Microsystem computer.

The film reader accepts color negatives, color transparencies or lithographic films, which it scans at a resolution of up to 3,600 picture elements, or pixels, per inch.

The digitized image can then be edited in a variety of ways using an electronic pen or ''puck.'' The film writer writes the altered image on new film - either color transparencies or color negative film - creating a high- quality second-generation original. Images can also be stored on 8mm videotape or transmitted electronically.

DeMoulin said the quality of the final product is indistinguishable from that of the original.

Premier operates on the red-blue-green continuous tone technology of film, rather than the cyan-magenta-yellow-black technology of graphic arts systems, DeMoulin said.

Kodak's final display in New York City's Grand Central Station - a huge photograph of a plump red apple floating behind the city's skyline - was made on Premier.

Making the composite picture the traditional way would have meant hours of cutting around the fine details of the skyline with a razor blade and then rephotographing it with the picture of the apple, said Robert Blakey of Kodak's Professional Photography Division.

Premier's zoom feature allowed the picture of the skyline to be enlarged, making it easier to edit tiny details.

The system, which will be sold beginning this fall for under $500,000, is targeted at full-service photo labs doing advertising work, magazine art or other large photo displays, DeMoulin said.

He said Kodak eventually hopes to produce smaller, simpler models to serve smaller labs and professional photographers.