GeoMapApp© Help
Using the Palette Tool
Centered in the Palette Tool is a histogram of the data visible in the Main Map Window showing the colors used for the data values. You may modify those colors using this tool.
You may view a movie tutorial (requires Flash software) demonstrating use of the Palette Tool.
| Palettes | Color Range | Shading | Contouring | Coloring |
Palettes 
Land and ocean areas may be colored using one palette or with separate palettes.
- select
to modify the ocean palette. - select
to modify the land palette. - select
to modify a palette for both land and ocean (default). - Click Palettes to view the palette menu. Click 'Make Custom Palette' to select your own colors.
- Click 'Save Custom Palette' to save your work.
- The saved palette contains the elevation and color for each tie point, and a vertical exaggeration.
Modify the range to be colored
The vertical lines in the histogram delineate the colored range.
These can be dragged to adjust the range.
Click 
to normalize the range to the minimum and maximum elevations in the DEM.
Click 
to reset the range to the palette's default range.
Shading
Sun Illumination may be toggled on or off using the buttons.
Some data, such as sidescan, is best viewed with no illumination.
The Sun Illumination tool modifies the inclination and declination of the sun. Drag the yellow ball around, or enter inclination and declination in the text fields. Even if separate land and ocean palettes are displayed, the same sun illumination is applied to both.
The Vertical Exaggeration tool modifies the shading contrast. Higher V.E. accentuates the shading. Enter a larger or smaller value for vertical exaggeration in the text field. The V.E. may be different for land and ocean.
Contouring
- By default, the coloring scheme is continuous
- the color for a given elevation is interpolated from the tie points. For discrete contour interval coloring select the adjacent button, which shows bars of color, and enter the color contour interval in the text box next to it 
. (After entering a new color interval, click the colorbar button to apply the change). To turn off the colored contour option, press the continuous color button. After a brief pause, the color change will take effect. 
To draw line contours, enter a contour interval in the text box next to the contour button 
and click the button. A dialog pops up for modifying the interval and elevation range contoured. The contour button then toggles the display of contours. If you want to change the range, you must first change the interval in the text box.- Color and line contours apply to both land and ocean.
Modifying Colors
Select a tie point by clicking its color box below the histogram, at the bottom of the dialog window. Then drag the bars in the color modification tool (H-S-B) to change the hue (H), saturation (S) and brightness (B) of the tie point. Try moving the saturation (S) bar upward first, then move the hue (H) bar to the color you want. Then make fine color adjustments by changing S and B.