I loved this look! And here is how you can achieve it in iScrapbook, too. The leaf is from the Lettering Delights Foliage Doodlebats. Please refer to my tutorials on using dingbats as images.
1. Duplicate your image at least 3 times. With the first image selected, click on the adjustment box and scroll to color. Choose your color and adjust your settings. This will be your lightest/ brightest shade of color.
2. Repeat above directions, using the settings for step 2. You can choose another fill color or simply click on the color box and use the slide beneath the color wheel to go darker. I like to go at least 1/2 the distance between my lightest color and the darkest shade.
3. Repeat the above directions, changing the settings as indicated. The color selection will be your darkest shade.
4. Stack your colored images beginning lightest (1) to darkest (3) on top. Draw your bounding box around the stacked leaves. In the dropdown menu, select ARRANGE. Because you have all of the leaves selected the box should say "group". If this does not happen try drawing the box again. Then, from your ARRANGE menu, select the 2 center ALIGN toggles (horizontal and vertical center).
5. To finalize your coloring, with the group still selected, choose FORMAT : GROUP.
You can now "jump in" and create the perfect pile of fall leaves!
Until next time!