LEAD:

As America is commemorating the 150 years of the Civil War, the biggest and most anticipated event is the Gettysburg National Reenactment July 4-7, where 15,000 “historical interpreters” and thousands of civilians from around the country will recreate the camp life, field battles and defining history of that fateful week in July 1863.

As part of the Gettysburg celebration, veteran photojournalist Steve Collegeman of Stuart, Florida, has been commissioned by the Gettysburg Anniversary Committee to document the event up close and behind the scenes. Unlike any other professional photographer, Collegeman will have complete 24-hour access by being embedded with the 3^rd U.S. Infantry.