Realism is hard to achieve, and landscapes are the hardest ( for me anyway ). 3 thing I would point out, 1. the terrain, is only one color, not very realistic. 2. the water falls, color's to flat no highlights at all. 3. the tree on the left is growing out of rock, just doesn't look very convincing. here's a place that may help you in your quest for realism, it's about 3D in general. check out the observations and tutorials. http://www.dvgarage.com/garage/a2d/a2d.php

Stephen Ray