This is a little experiment; I take a cube put a sphere inside apply crystal texture to both an duplicate it, after that I edit the refraction index of these objects the refraction index of left cube is 3.5, the left sphere is 1.5 the inverse for the right object, the right cube is 1.5 and the right sphere is 3.5 both object act as a lens and as parabolic mirror, but one seem to be divergent the other convergent. The Radiance map is from dan Meyer; http://www.fictionalhead.com http://smashmethod.deviantart.com/art/High-Res-HDRI-Map-Pack-1-9597501 In a previous image; http://www.renderosity.com/mod/gallery/index.php?image_id=1919656&user_id=119539&member&np I received a constructive but negative comment about the realism of the wood texture I used. Because of that recently I tried to make a better wood texture, I sometime need to make huge print of my image, that mean I need a big texture map, I start with PS create an image 12,000 by 9,000 pixels, used a lot of layer with noise and radial blur, colours, I mix these layer in different way ( overlay, difference etc ) sometime resizing the layer, some time using cloud layer mask until I get a wood image I like from that I also create a bump map by desaturate and changing the contrast and brightness, with these 2 images I build my wood texture in Carrara, the resulting texture is huge in size around 250mb but the render is good even in poster size render, I kind of proud of it ;-)