Conforming to an age when discos are held at shopping malls and Saturday afternoon at the department store is more of a cultural experience than a necessity, Woodward & Lothrop Inc. spent two years and six-digit figure to develop a new corporate identity and a way to project it.

What the retailer ultimately learned, however, is that like the old Woodies logo, marketing research sometimes has holes in it.

Woodies imagemakers came up last August with a more modern look for their stores, different colored shopping bags (plum, forest green, dark blue and rust) and a logo with futuristic type - the Os colored in and a slash mark instead of the historic ampersand.

What they got from consumers were reactions like, "childish and immature," said marketing vice president William D. McDonald Jr. yesterday. Consumers saw the big "O" without a hole in it and said it looked "like what children do in comic books," McDonald said. Customers said the new symbol represented "an insecure position, like people who doodle," McDonald recalled at the firm's annual meeting.

But there's more to the image peddling than meets the eye - or the O. Customers liked the new colors, remodeled stores and other components of the image campaign. But from in depth interviews of 500 persons, executives concluded that the filled in Os threatened to pull the store's positive identiy down, McDonald said.

The department store company's executives were faced with a difficult choice: Pump in more money to convince the public that the filled-in Os were not childish, but what the company stands for, or "just unfill the Os," McDonald said.

Yesterday, they unfilled the Os and brought back the ampersand.

After the Os were filled in, the slash mark had to be replaced because visiually it made the words run together, McDonald said.

"The filled-in Os as a negative in the program was small," McDonald said. But the longer the Os were kept filled, the worse the store's image would become and the more and more costly it would be to change, McDonlad said.

As a result of the change last August, even with the colored in Os, customers saw the store as "innovative, out in front," McDonald said. "People see us as a more contemporary, aggressive leader."

McDonald said the actual cost of changing from the old overlapping Os and ampersand to colored-in Os is in dispute because some of the changes in products, such as shopping bags would have been done anyway. Store names on the Chevy Chase and Lake-forest stores were already changed to filled in Os and they will stay that way for a while, McDonald said.

Only one truck carried the logo with the filled-in Os, McDonald said. As trucks and store equipment are repainted or replaced, the new logo will be substituted, he explained.

The cost of the new logos will come out of the store's marketing budget and will not be passed on to consumers in higher prices, or to stockholders, McDonald added.

With increased competition from new stores in the area like Blooming-dale's, Neiman Marcus and I. Magnin, "Good Old Woodies wasn't good enough," McDonald said. The store now is meant to "feel a close relationship to your lifestyle."

McDonald said Woodies' management now believes it has the right logo to go with its new image and a new logo is not expected soon. The lifetime of a logo is usually five to ten years, "or as long as you have a viable identity going" McDonald said.