Adding Colour, Lights and a Backdrop to the Intestines

I've been experimenting with light, bump mapping and backgrounds to complete the intestines set.

 First render looked interesting but a little dark and didn't match the theme and atmosphere of the overall animation. This render has both sets of intestines back light with a directional light turned up high in the intensity, however this is still too dark.

 In Photoshop I painted a very simple matte painting to be the backdrop of the set. The main point of this painting it to help back light the intestines along with the directional light.

 The renders after that started to work better than before, yet the intestines are still a little dark.

 I altered the colours of the intestines to make them stand out more against the background.

 This is the last render I've done. Though it looks a lot better than before I think it can still be improved. I might need some help with this one.