Imported the fog into the tree scene and faded the opacity as the tree comes into focus, using a Fast Blur effect. Used the effect "light rays" for a dimly lit sun, which gives the clip some ambience and balance. Quite pleased with the outcome however I think the camera tracking should be a lot slower so more focus can be paid on the detail around the bottom of the tree.
Tree Render.
Rendered a fog test in After Effects using a combination of fractal noise and mask layers which have been feathered to enable the gradient effect. I hope to use this in some of the first scenes of my film, namely the mountainous scene with the castle. I am quite pleased how this turned out. This effect was loosely based on a tutorial from ae.tutsplus.com
Fog Test