The grid density is controlled by the number and spacing of grid lines. The greater the number of grid lines for a given grid length and the smaller the grid spacing, the higher the grid density.
Higher grid density results in more accurate maps, but takes longer time to compute. Be sure the grid density is high enough to define the smallest detail you hope to display on your map.
Under Gridding Geometry in the Gridding dialog box, enter a value in the Spacing and Lines text boxes for the X- and Y- axes. Spacing is in map units.
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