On View : Where the Hartman Is : AFTER WAKING UP AT 3 A.M. FOR 12 YEARS, HE’S BEEN TAKING HIS TIME ‘REDISCOVERING AMERICA’

Eight years ago, David Hartman made a career move that few people in his position would have been willing to make: He left his high-profile, high-paying job as host of ABC’s popular “Good Morning America” in order to spend more time with his family and to concentrate on his documentary film business.

In the process, Hartman went from being one of America’s favorite breakfast companions to relative anonymity. But today he has few regrets about making that momentous decision, especially when he recalls his hectic work schedule in those days. Hartman would often leave home at 3:30 a.m. and return at around 8 p.m.

“I did work [a lot of hours],” recalls Hartman, who hosted the New York-based “Good Morning America” from its inception in 1975 until 1987. “I thought that would change, but it never did because if you’re going to do a show like that, well, you have to put in those long hours. I was never home. At the time my [four] kids were between the ages of 5 and 12 and I just wanted to be around more. [Plus] new management had come in and was going to change things, which was fine. But I thought if I was going to go that was a good time.”

Since leaving the early-morning talk-show circuit, Hartman says he’s struck a positive balance between his family life and his passion for writing, producing and hosting documentaries. Work-wise he’s devoted much of his energy to his New Jersey-based production company, Rodman-Downs Inc., which has presented numerous network, cable and public television documentaries over the last 21 years.

Last year, Hartman also replaced Roger Kennedy as host of the Discovery Channel’s “Rediscovering America.” This season Hartman will be narrating three more segments in this sporadic American history series. On Tuesday, the season’s premiere program explores the construction of the 1,500-mile-long Alaska Highway, which was built in only eight months during World War II. The highway was developed to help the state defend against a possible Japanese attack.

Hartman speaks with great enthusiasm about his experiences working on “The Alaska Highway” documentary. One of the most fascinating aspects of developing the project was learning about the African American military units that helped build the highway, he says.

“Of the 10,000 Army construction workers, about 3,500 were black,” Hartman notes. “They were in segregated units and their participation in this history is not well known. I went to North Carolina to interview two of these men who are in their late 70s and they’re in better shape than just about anybody. One of them is the national singles and doubles men’s tennis champion for those over 75 and the other one is just a rock. He’s one of those guys you touch and his muscles just ripple.

“Still,” Hartman adds, “it’s remarkable that not many people died [during construction of the Alaska Highway]. The conditions were horrendous. They lived in tents and they had to deal with the cold and insects.”

Hartman and a film crew spent about a month in Alaska and Canada’s Yukon Territory working on “The Alaska Highway” as well as a documentary on the thousands of people who journeyed to Alaska’s Klondike River in search of gold in 1896. The latter program will be the second segment in this season’s “Rediscovering America” series, airing Feb. 7. The season’s final program will chronicle the life of Benjamin Franklin; it has a Feb. 29 air date.

Hartman’s involvement with documentary television began in 1974 when he produced and hosted a special called “Birth of Babies” for ABC. The documentary was the first to show an actual childbirth on television. At the time, the Duke University economics graduate was known as an actor. He had appeared in the TV drama “The Virginian” in 1968-69 and “The New Doctors,” the medical part of the series “The Bold Ones,” between 1969 and 1973.

The inquisitive Hartman says his move into documentary film work was an outgrowth of his intense desire to make realistic and informative television.

“With ‘The Bold Ones’ I didn’t do any writing but I did a lot of [medical] research,” says Hartman, 60. “After the series was canceled, I traveled around speaking and working with various medical organizations. I also spoke before Congress about the relationship between the medical and entertainment communities in getting medical information to the public. Then ABC came to me and asked me if I wanted to produce ‘Birth of Babies.’ That’s why I started my [documentary film] company.”

Hartman subsequently played a high school teacher in “Lucas Tanner,” which aired on NBC from 1974 to 1975. But when “Good Morning America” offered him the job of host he decided to leave the acting profession for good. “I always thought that acting was the aberration for me,” he offers.

Last month, Hartman returned to “Good Morning America” for a special show celebrating the program’s 20th anniversary. He says he conducted more than 12,000 interviews during his tenure with “GMA.”

Would Hartman consider returning to the rigors of doing live television now that two of his children are in college and the other two are in high school? “Possibly,” he says. “There have been a number of [offers] through the years. Should the right circumstances come along now, yeah, I would consider it.”

“The Alaska Highway” airs Tuesday at 10 p.m. and 2 a.m. on the Discovery Channel; it repeats Dec. 17 at 2 p.m. and Dec. 21 at 10 p.m. and 2 a.m.