I have a problem with the lights,because this is a topic that I have never studied well. I don't understand because the scene that I created is not lighted very well. I'm using the sky texture as background in cycles render. I have also placed a sun light on the scene and I have increased its strenght,but it seems that it is not working. Problem is that the facial features,the shoes and the hands of the boy are too dark. Instead,the girl is better lighted...can you give me some suggestion ? thanks.
You can find the blender file here :
NB : The character models come from blendswap. I have only modified them a little. Credits goes to the original authors.