The transit authority staff, preparing for one of the biggest changes ever in the Metrorail service pattern, is trying to make eye contact with its riders.

To plan for the proposed split in the Blue Line and the later addition of the Dulles rail extension, Metro is studying how people pick up visual clues about which train to take. Barbara Richardson, Metro’s assistant general manager for customer service, communication and marketing, announced last Thursday that the transit authority also is bringing back its original mapmaker, Lance Wyman, to revise the well-known map.

How often do riders use the map, and what do they use it for? On the trains, there are big maps at the ends of the cars and smaller ones near the center doors. In a crowded car, some riders will stand on tiptoes and peer at it. Others need to get real close and study the text. Most commuters are taking the same trip every day, and they ignore it, unless a tourist asks for directions. There’s likely to be a lot of map-gazing during the upcoming Cherry Blossom Festival.

The Greater Greater Washington blog is holding a contest to design a better Metro map.

The rules established by blogger Matt Johnson, who also has his own blog called Track Twenty-Nine, include requirements to show the new services and the new stations. For the Blue Line split, which could occur in mid-2012, that means showing some rush-hour Orange Line trains going to Largo, and some Blue Line trains going to Greenbelt. As an added difficulty factor he asks contestants to show the planned “virtual tunnel,” allow riders a free transfer if they walk between Farragut North and Farragut West.

The contest map also needs to show the future route of the Dulles Metrorail line. Johnson notes that the Metro board hasn’t named that line yet, but since so many people are calling it the Silver Line, your map should as well.

You can pick which of these elements to show and how to show them: Names of the lines, their end points, other transit connections and parking, jurisdictional boundaries, natural features, monuments, the Capital Beltway and airports. (You know the current map like the back of your hand, right? How many of these elements are on the current map and in what form? No peeking.)

The contest deadline is April 30. Metro is going to need more time than that for its own effort. At Thursday’s meeting, the transit authority asked that the local jurisdictions make haste to submit any station name changes they desire. That makes me shudder.

The Metro map presentation is a bit like the Constitution: It conveys about as much as it needs to and then let’s people talk through the details. In Metro’s case, station managers and long-time riders can relay the details to the newbies. I’m glad there won’t be any equivalent of a constitutional convention to redesign the Metro guide.

Wyman’s original map is a masterpiece of simplicity and discipline. Before he did the Metro system map, he created the map for the Mexico City subway. Zachary M. Shrag points out in his book “The Great Society Subway” that many of the world’s stylized transit maps are descendants of the London Underground map of the 1930s.

“These maps are not accurate, topographical representations of station locations,” Shrag wrote. “Rather, they are diagrams, designed primarily to show the ordinal sequences of stations along a given line, as well as transfer opportunities between lines.”

So be it always.