Two of the most useful colour correction tools are “Change Colour” and “Change to Colour.” The main difference between these two tools is that “Change to Colour” allows you to pick the colour that you change to, whereas with “Change Colour,” you change the hue of the colour using a value.
While I don’t use it 100% of the time, I prefer the “Change to Colour” tool as it gives a bit more control in general.
One of the shots which required a large amount of colour correction was a shot which involved Magneto floating in front of a building.
The animation I was given had colors which greatly varied from the colors in the trailer, largely due to limited Lego colour choices. For example, the green of lego trees does not match up with the green of the trees in the actual shot. There are also yellowish leaves in the shot, which would be very difficult to recreate without any colour correction.
The first step was to mask off the left tree from everything else. I duplicated the layer and made a mask around the tree. I applied a slight feather around the mask so that the surroundings blended in if there were any changes that occurred to them during the process. I then selected the “Change to Colour” effect under Effects>Colour Correction. Once this was added to the layer, I chose the colour that I wanted to alter, in this case, the green colour of the tree. Next, I changed the “Change” from “Hue” to “Hue & Saturation.” Because not all of the tree is the exact same colour, I adjusted both the “Hue” and “Softness” values until I achieved a result I was happy with.
Not everything requires masking, however, if there are more than one area in the shot that have the same colour (but need to be altered differently), masking is probably the best approach.
Here is the final result: 
As you can see, I changed the colour of the building, the other tree, and the sky in the background to match closer to the original shot.
Jedimastersoda 