CG Art or Real Photo Image?

Which one is of the three images is computer generated? Is it the planet? The LCD screen? or the watch? If you are good you will know that all of the above are CG art and done in Adobe Photoshop. Yes, no image above came from a snapshot, they were all made from scratch using Photoshop. If you have the patience and the drive you can create images like the ones featured above, they are actually quite easy to make. Here are some tutorials I've found : Create a Watch, Realistic LCD HDTV, 3D Planet. 

Check out these tuts and I am sure you'll be addicted to Photoshop, like me :P