Some 30 artists set up their easels all over Annapolis this past week, from quiet back alleys to the lawn of the Maryland State House. Intrigued local residents stopped to chat or simply stare.

"Need a model in the picture?" one man shouted from across the street to Karen Scannell, 40, a painter from Ireland.

The artists came to Annapolis to compete for a $3,000 prize in an open-air painting contest. Organized by the Annapolis-based nonprofit Maryland Federation of Art, the competition celebrates "plein air" painting — that is, painting outside.

The artists — selected earlier this year in a juried application process — began scouting out locations to paint Monday, and they had until Friday to complete their works. A judging and awards ceremony was slated for the evening of Friday, June 27, and a gallery show of the finished works is being held Sunday, June 29.

Lynn Mehta, 51, of Alexandria, Va., painted a strip of blue sky between two old brick houses Wednesday afternoon. "Look, I can't see the [paint] colors," she said, moving her palette into the shade. "They get washed out in the sun."

Shifting sunlight is one of the biggest challenges in plein air painting, but also part of its appeal. "Even if the light changes, you're supposed to remember" how it was before, Mehta said.

Scannell said the light in Annapolis changes more slowly than in Ireland, where she is from. There, painters must keep up with clouds that sweep across the landscape.

"I'm getting a bit lazy," she said.

Scannell is the only competitor this week from outside the U.S. She learned about the competition from David Diaz, president of the Maryland federation, who has attended an Irish plein air festival for the past five years.

Such networks of plein air painters are common, said Mehta.

"It's sort of a small pool of us, so we all end up in the same events," she said. "We get familiar with each other's work, we paint together."

Formal organizations also help maintain the plein air community. The first Paint Annapolis event took place 12 years ago. When the Maryland federation took over this year, it added a "Nocturne" night-painting event Thursday that was open to the public.

The week also included a Dueling Brushes two-hour "quick draw" event that was scheduled for Saturday, June 28, as part of a daylong exhibit and festival at Circle Gallery in Annapolis. Work from Dueling Brushes will be on display July 1-15 at Maryland Hall for the Creative Arts.

The first plein air painters were 19th-century impressionists, Diaz said.

"It came along the same time as tube paints," which were more portable than paints ground in the studio. The camera had also been invented, freeing painting from strict representation, Diaz said.

Plein air painting offers a different way of seeing the world than photography, Mehta said.

"A photograph gives you different information than what you see" with your eyes, she said.

Scannell said she would rather make a painting than take a photograph.

"When you're painting, you're listening to the birds, talking with the locals, using all your senses," she said. "You get a deeper impression."

If you go

The Paint Annapolis exhibition and public reception, displaying works created during the plein air weeklong event, will be held from 10 a.m. to 4 p.m. Sunday, June 29, at Circle Gallery, 18 State Circle, Annapolis.

For details, call 410-268-4566 or go to mdfedart.com/pages/paint_annapolis.php.