"With 2008 being an election year, we feel confident this notion has strong legs and will continue to be salable, if shot the right way," said Meg Azaro of Spark Visual Research. The New York cool-hunter cautions that green can be difficult to shoot without doing the obvious. There is a difference between being green and shooting a picture that looks green.

"Organic clothes made of hemp might be green, but they don't distinguish themselves as being green in an image. As an image maker, your goal is to come up with visual cues that reek green," she explains. For example, natural light through windows without curtains can give a photo an optimistic feel. According to Azaro, optimism goes hand-in-hand with environmentalism, while sunlight brings in the concept of alternative energy.

Recent Corbis data says creatives turned to visuals of nature to convey respect for the environment. The company reported increased demand for close-ups of water droplets, landscapes, images of eco-tourism, tree-huggers and people in natural settings.

"It is no longer just the color, just the penguin, just another cliché. Consumers are hip to green hype and are looking for a more sophisticated view of a green world," said Denise Waggoner, vice president of creative research at Getty Images. Waggoner thinks that consumers have become inundated and hardened, because green has become a ubiquitous sales tool. "Everyone is preaching to us, from governments to our favorite products, like coffee, chocolate and shampoo, about the action we should be taking to save our planet."

To provide photographers with practical guidance, Corbis and Spark have published Global Greening and GREEN, respectively. Getty Images just completed a four-month study on visual trends and the environment. Getty also partnered with Yankelovich for a consumer-oriented study. The findings will be released some time this month in Getty's next MAP Report.

While many stock photographers and agencies are concerned with shooting and selling green, some want to be green. Fast-growing U.K. sales platform Alamy has run a greenhouse-gas reduction program since 2004. In an effort to become greenhouse-gas neutral, Alamy invests in videoconferencing and electricity from renewable sources whenever possible. It also monitors travel and incorporates energy reduction targets in management objectives.