Those of us for whom the enigma of the D.C. bus system has lost much of its charm are delilghted that we finally have a bus map. Indeed, two eight-color Metrobus guides, one for D.C. and Maryland, the other for D.C. and Virginia.

They aren't perfect, but they're awfully nice -- and they sure beat 154 separate timetables for giving you the big picture. The first printing of 200,000 copies is on sale for $1 a map. (My initial purchase of 10 copies almost gone -- absorbed by the neighborhood like water in a desert, the Roseta stone of getting places.)

"You mean you can get there from here?" cried one map-snatcher, on learning of a bus that leaves Wisconsin and Western, passes through Chevy Chase, crossess Rock Creek Park on Military Road and ends up at the Fort Totten Metro station.

"So that't where Ivy City is!"

"Did you know that the D8 becomes the D2 and the D4 when it's westbound?"

"Look how the T routes split and make a sandwich of the NIH."

Best of all, you can see where the bus you take to work comes from before it picks you up and where it goes after it lets you off -- information particularly useful if you want to backtrack a few blocks to assure yourself of a seat.

Hang on to those timetables, though, because a sole source of information the map isn't. In a system with over 12,000 bus stops and 1,7000 route variations, it's not surprising that the map doesn't indicate where along a route the bus stops, or how often, or when service begins and ends.

While the graphics are lovely and for the most part easy to follow, at the risk of sounding quibbling, the pastel colors are barely distinguishable if you suffer any degree of color blindness, a problem I wasn't even aware of until I showed it to a color-blind neighbor. And it's a big map, one you're not likely to find easy to study on a windy street corner.

To have come this far, however, seems nothing short of miraculous to those of us who have heard for years that the frequent route changes associated with the expanding Metrorail system made issuing a bus map impractical.

One reason for the miracle, perhaps, is that last year the eight signatories to the Metro Compact passed a resolution that would restrict route changes to twice a year, at the time of "operator picks" in June and January, when bus drivers choose their routes for the next months. Whether the eight jurisdictions will stick to this resolution -- insiders say it lasted about a month, and already the L2 is stopping short of Van Ness Center to save money -- remains to be seen.

But it did make possible a bus map that Metro spokespeople say is "99 percent accurate."

Some background: In January 1980 Metro awarded a $34,000 design contract to Michael Hertz Associates, the graphics consultant who designed New York City's most recent, and widely praised, subway map. Costly?

"To say that we did not do well financially is an understatement," says Hertz, 48, who did not realize when bidding that designing the map would require such a massive job of editing information.

Toward the end of the nine months it took to design the map, Hertz -- who for 10 years was Walt Disney's art director for motion-picture advertising -- had 12 people working on it. Twice the designer finished the job, only to have local governments make changes in their services. In the end, Hertz's office managed to show 350 routes, omitting only oddball lines that provide minimal service.

"The girl who did the insert became obsessed with arrows," says Hertz. "We all became obsessed. When we finally finished the job, three of us drove down to Washington and took a wrong turn. The only way we could find our way back to the Ramada Inn where we were staying was to follow the B6 bus, which we knew went right by it."

And now for the big question: When will Metro tackle the bus stop signs?

One of the peculiarities of life in Washington is that the traffic signs tell us more than we can possibly read from a moving vehicle, while the bus signs tell us nothing. D.C.'s bus stop signs are visible and classy, but they achieve this look at a cost: lack of information, except that a bus stops here.

Nothing makes a newcomer to town feel more like an outsider than a bus sign that implies an insider's knowledge of the system.

How do the millions of visitors who pass through the city each year figure out how to get places and why certain buses keep passing them by?

Metro, according to Ralph Frisbee of the office of marketing, has two basic answers to question about why they don't post more information at the bus stops: (1) No information is better than wrong information (the routes are always changing), and (2) They don't have enough manpower to keep information up-to-date at the 12,000 bus stops in the system.

There are six people assigned to bus stops, with most of their time spent on maintenance. Perhaps if more manpower were budgeted toward posting bus stop information, Metro could cut down on its 57 operators who handle an estimated 45,000 calls a week. (Not counting those of us getting a 15-minute busysignal while the bus of our dreams sails by.)

Another problem is that the design of current bus signs is not adaptable to showing bus schedule and route information.

At 50 pilot sites along 10th Street NW, and at Union Station, Metro is experimenting with a more flexible, four-sided bus sign with space for maps and schedules. Whether this particular project works out or not, the general principle of providing information at the point where bus connects with rider seems worthy of encouraging.

Washington is a lovely city to see by bus. And this new bus map should make it easier to find one's way. All that remains now is to demystify the bus stops.