[OpenLayers-Users] Another NooB Q - Re map position

[Arnie Shore]

Folks, in a very basic OL/OSM script of mine, the map center is showing 
up about a mile from the point the coords I've used represent, these 
coords being (a) obtained from a GMaps app, and (b) confirmed by my 
using the online click-handling example.

My centering function is =>

map.setCenter(new OpenLayers.LonLat(-76.5, 39.01)
  .transform(
    new OpenLayers.Projection("EPSG:4326"),
    map.getProjectionObject()
    ), 13
    );

What am I doing wrong?