The man behind the camera told his subjects NOT to smile -- right after he asked them to strip. But this was not your ordinarily group portrait.

The latest work by photographer Spencer Tunick gathered 1,840 people, baring it all in Austria's Happel Stadium, one of the venues of the European Soccer Championships that begin next month.

"Stay very still. Don't move," the Austria Press Agency quoted Tunick as telling the crowd as he went to work. Other requests from Tunick: no sunglasses, no underwear -- and no smiling.

Much of the hours-long photo shoot had little to do with soccer, with naked volunteers assuming different poses at the behest of the artist. But at least one of the photos had them with the ball, men first and then the women.

The stadium will host seven of the Euro 2008 soccer championship matches being staged by Austria and Switzerland. Among the games being played at Happel Stadium is the June 29 final.

Tunick has made a name for himself with his works featuring hundreds of naked people at unusual venues.

He described Sunday's shooting on his Web site as combining "the spirit of sports, the grand sweeping waves of stadium architecture and the abstract relation of the human form to modern structures."