The lights went out at the Ralph Lauren show in the Hotel Pierre Thursday night. There was hardly a murmur from the 3,000 people jammed into the ballroom, not even from the 200 or so photographers on their knees at the edge of the runway as the spotlights faded and the bank of television cameras ground to a halt. It was Ralph Lauren at his best, the strongest of this week's fall fashion shows, and the huge crowd was willing to wait quietly for the repairs to be made.

What they had seen up to then was Lauren's new chapter in his Americana saga that in the past has saluted the Wild West cowboys and Sante Fe Indians and this year zeroes in on colonial America, with old quilts made into skirts, sweaters with American folk art patterns and new versions of his antique lace blouses.

When the lights went back on it only got better. Most of Lauren's designs are lean and long, but even when skirts graze the bottom of the calf they are eased enough to walk comfortably. A tweed Norfolk jacket with a long button-front skirt in a checkered pattern, a lace jabot blouse underneath and high-button shoes epitomize the look. He's got the best new blazer around, with narrow lapels and three low buttons, and the sleekest dresses for the office in gray flannel, as well as a tuxedo dress with satin collar for dinner.

"After all the layered clothes, what is sleek and simple looks right to me," said Lauren. He isn't alone.

Halston, a master of clean, simple clothes, has varied some of his shapes this fall only slightly. Some jackets have bigger lapels or taller collars, another jacket curves up in the front, and the poncho, which he sells as if there were money sewn in the seam, shows up in more variations in cashmere knit and doublefaced wool.

But Halston's big news is that he has studded much of the fabric, from wool jersey to Ultrasuede to cashmere, with nailheads of silver and gold. "It makes the fabric a little more special and means the clothes a woman might wear to the office would be terrific at dinner," said Halston.

In a season when less is more admired, it comes as no surprise that Ronaldus Shamask's clothes are getting a lot of attention. He's an admirer of the late Charles James and, like James, builds shapes with his clothes, sometimes layering flat planes to achieve dimension, and at other times using angular and spiral cuts to achieve a precise shape. Huge collars grow into hoods, pleating unfolds like intricate origami, spiral seams shape a sleeve or trousers.

As his busines is beginning to grow--Saks-Jandel will bring the designer and the collection to Washington in May--the Shamask clothes have become more wearable, but admittedly take some time to understand. At yesterday's show in the auditorium at the Fashion Institute of Technology, the music and the stark white background combined with the look of the clothes to give the impression they had been inspired by religious orders.. Some of the first garments looked like a nun's clothes, and others were inspired by medieval wimples or chasubles. But because the shapes are so simple, the clothes look very modern.

Even before the first patchwork quilt skirt made it down the runway, Lauren said, he got his first hate letter, condemning him for destroying works of art. "I'm a lover of American art, not a destroyer of it," insisted Lauren, who has bought the quilts for his patchwork skirts, designed to be worn at home, from collectors and dealers. "I've taken the best quilts and given them a new dimension. More people will see them and admire them. And besides, how many quilts can you put on a bed?"