To change the color gradient, you use the Palettes portion of the Uber Browser window. We have a section in the documentation entitled Color Palettes which goes over some of the methods to change palettes. In short form, though, if you're looking for a straight-line gradient you can:
- Choose Window > Show Uber Browser to bring up the Uber Browser window
- Click on Palettes to bring up the Palettes panel
- Click the + button to add a new palette and give it an appropriate name (such as Green scale)
Select the Green Scale palette in the window
Below the list in the Palettes panel, there is darker grey area that shows all of the colors in the palette. Initially, it is empty and shows only a light gray outlined box to the left and the preview in the top portion of the panel will show a black and white bar indicating a completely transparent palette.
Click on the light gray outlined box to create your first color and then double-click on it to bring up the Color window
When you do this, the gray outline box will move to the right, indicating you can add another color to the palette later.
In the color window, select your first color of green.
The preview in the top portion of the panel will show this color all the way across
- Click on the light gray outlined box again to create a second color area, and double-click on it to bring up the Color window
- In the color window, select your second color of green.
By default, the palette will interpolate between all of the colors in the palette, creating a smooth gradient from the first color to the last, stepping through each other color in the palette on the way. You can make the palette function as a step palette (where there are only specific colors and no interpolation) by clicking on the toggle just above the colors.
You might also check out the Color Brewer 2 site which has some great palette tools. The Cartographica help on Color Palettes will show you how to paste these into Cartographica's palette window.