Setting a key frame for the contrast/gain settings in Nuke

Setting a key to change the range values in Nuke.
For this shot the iceman melts in the foreground - it's the end shot of the melting sequence and I wanted to play with the opacity, so I set a key frame at the start (highlighted red rectangle on the left of the timeline below) and another at the end and changed the value sliders on the right.
Using the ID passes, I was able to isolate the men, by selecting the rgba_green channel in the ranges of the colour correct node, and apply the transformations.
Image below with full contrast/gain values

 Image below with the contrast/gain values adjusted, which gives the appearance of a fading colour

NUKE: isolating CGI elements using an ID pass

Using an ID pass, to isolate a CGI element within the scene, to create a blur and colour adjustments, to just that particular area.

In this case the tree bark. The render was too sharp, so I adjusted the ranges, just on the rgb_red channel (the tree geometry had a red surface shader applied to it in Maya prior to render)

Image Below:

ID pass adjustments. Red rectangles highlight the ID pass in the node graph, the final image in the render view and the range and rgb channel selector on the right.

Bark with the blur node deactivated. Bark looks sharp

Blur node on bark activated

Connecting the ID pass to the colour correct node, so that the individual R G B channels can be selected