FRANK SINATRA, MY FATHER. By Nancy Sinatra. Doubleday.339 pp. $50.

NANCY SINATRA gives us fair warning in the introduction to Frank Sinatra, My Father, her hefty new coffee table tome on the most infamous saloon singer in American history, Ol' Blue Eyes himself.

"I am not a biographer," she states. "I am a collector and an observer and a daughter . . . This is a love letter . . ."

Just in time for Christmas and Sinatra's 70th birthday, and presumably to head off Kitty Kelley's much ballyhooed and definitely unauthorized upcoming biography of the crooner, Nancy Sinatra's memoir is by far the glossiest and goopiest effort by a celebrity offspring yet.

In fact, the only thing that will save this book from the remainder bin is the photographs: wonderful vintage stills and snapshots of the singer culled from family albums interwoven with film posters, album covers, candid shots from recording sessions and haunting portraits of a man who, having endured more media attention than perhaps any other entertainer in recent history, still remains a mystery.

It is no wonder then, that Sinatra is even an enigma to his daughter, who comes off as a whining, spoiled child still trying to get her father's attention. And no wonder. A powerful figure who flitted in and out of her life, an elusive man "in a black bow tie and black patent leather shoes who was always going away," Sinatra is portrayed as a mythical figure who could do no wrong, even after he left his first wife and three children for Ava Gardner. Even if he did prefer the bright lights of Vegas casinos, the camaraderie of politicians and the back-slapping shenanagins of the Rat Pack to the intimacy of family life, Sinatra -- in the eyes of his daughter -- never fell from grace.

By his very absence, whether calculated or not, Sinatra's image grew to mythical proportions, and it is this larger-than-life tone that makes Frank Sinatra, My Father so unbearable and, ultimately, so unbelievable.

It is simply too much for the reader to swallow that Frank Sinatra, a man who has done it His Way for the last seven decades, a man whose hot temper and questionable manners have often made him Chairman of The Bored, a man who still refers to women as "broads," can be so benign. Sweet, sensitive, "a blend of strength and softness," he sounds like a dish detergent. Can this be the same man who once called a woman reporter a "two dollar whore" and snarled to Entertainment Tonight's Barbara Howar, "You're all dead."?

GENEROUS to a fault and consumed with performing good deeds, Sinatra as portrayed here makes Mother Theresa look like Alexis Carrington. Indeed, the singer's much heralded secret gestures have become so well documented I'm beginning to get suspicious.Any man who would allow so much praise for his charitable concerns (the back of the book lists not only his records and films, but over 50 of his favorite charities) should drop this Mr. Anonymous pose.

And don't expect any insights into why Sinatra's reputed Mafia ties have dogged the singer for most of his professional life. His daughter says it's all in the minds of the media, which have persecuted her father for years. She also goes on ad nauseum about Sinatra's lack of prejudice, fighting for blacks and Jews. She neglects to mention that in 1981 Sinatra ignored a boycott from anti- apartheid groups and pocketed $1.5 million for nine concerts in Sun City.

For the record, he was born Francis Albert Sinatra on December 12, 1915, in Hoboken, New Jersey. Weighing 13 pounds at birth, the child nearly died before the doctor placed the forceps around his head, leaving scars on his ear, cheek and neck. "Perhaps in those few moments lie some of thces behind the impatience, the steam roller ambition, his exhausting pace, extravagant style," his daughter writes.

His mother Dolly was an overbearing woman, his father asthmatic and shy. Young Francis grew up, we are told, a lonely child who was determined to better himself. He spent hours listening to crooner Russ Columbo and his idol, Bing Crosby, on the radio and eventually decided to make music his career. He quit high school in his senior year, married his sweet heart, Nancy Carol Barbato, and began singing in roadside taverns for $15 a week. When Sinatra was discovered by bandleader Harry James, the singer's wife was pregnant, living on fried onion sandwiches and collecting empty Coke bottles to buy food.

By the time his daughter Nancy was born, in 1940, Sinatra was on the road with Tommy Dorsey's band. "Already ," she writes, "I was being prepared for having to share him with the rest of the world . It was the start of what became one of the themes of my life: A father who was always going away. My father was always saying goodbye."

While Sinatra was perfecting his unique phrasing technique and driving the bobby soxers into frenzies, his family led a normal life at home in Jersey City. And while fans were collecting snippets of Sinatra's hair from barbershop floors, his daughter was staring at a framed photograph of the singer, propped on a living room chair.

"He was," she writes, "a voice on the radio most of the time or a picture in the newspaper."

In 1944, Sinatra moved hs wife and two children (by now Frank Jr. had been born) to Los Angeles. It was a charmed life, palm trees and swimming pools and hobnobbing with the sons and daughters of the famous. "Those earliest days in L.A. were my happiest as a child. Every thing was so nice. I wasn't yet fully aware that my dad was heading for something beyond stardom, that he was special and that I was, therefore, special too, some sort of minor celebrity myself."

Buthe heady days ended when Sinatra fell in love with Ava Gardner and left home. His daughter, in a poignant note, recalls meeting the actress for the first time. "My heart melted just looking at her. I was only a kid. I didn't know about beauty -- that awesome kind of beauty . . . she was just the most beautiful creature I had ever seen in my life."

At the age of 14, Nancy Sinatra accompanied her father on a tour of Australia. It was then, she writes, that her love affair with her father began to go sour. Looking in her father's drawer for stationary, she discovered "some intimate ladies apparel' ' belonging to one of the women in the show. "For the rest of the trip I was destroyed," she writes. "He had cheated on me."

Her father went on to marry actress Mia Farrow ("she called him 'Charley Brown,' he called her 'my Mia'") and in 1976 wed his current wife, Barbara Marx, who is portrayed as somewhat of a goldigger.

In fact, Nancy Sinatra says she cried for a week before the wedding (disapointed that the singer did not remarry his first wife as the family had hoped) and reveals that during the ceremony, when the judge asked if the bride took the groom for richer or poorer, Sinatra announced, "richer, richer."

She says for years she had trouble adjusting to the marriage. Her father, who once showered her with expensive gifts all the time, was now gifting his new wife. "I felt I was losing him," Nancy Sinatra pouts.

The author went on to achieve her own minor celebrityhood with a hit record "Boots" and a few minor films. She even played Vegas while Daddy was playing elsewhere down the Strip. Mostly, Nancy Sinatra has lived in the shadow of her famous father all her life and is still caught between resenting his true mistress -- fame -- and cashing in on it. With this book, she manages to do both. Even if father and daughter are still only strangers in the night.