I am wondering if there is a way to adjust color in certain elements but not in all of them.
Here's an example:
I have a bowl of tomato soup that I really want to make more red, but don't want to adjust the bowl. I could just roto the soup and motion track it, but that would take forever. Is there a way to grab all of the red and adjust it some other way?
Also, what you can try is a color range key together with a Refine Matte. Duplicate the layer, apply all of the above to key out the "soup" in the top layer and adjust the bottom layer to get the red you need using Hue/Saturation or any of the other Color Correction effects that come with AE.
Try duplicating your video layer. On the bottom layer adjust the red levels or the saturation to the desired effect. On the top layer, use a keyer (I suggest color range) and key out your soup. Adjust your matte (fuzziness if you use color range) Providing that there aren't any other objects in your shot that are the same or a similar color as your soup, this should give you the desired color effect you are looking for.
You could also track a matte and on a second layer adjust the saturation and color values. This will also give you the look you are wanting.
I'd recommend using a color grading tool like Synthetic Aperture's Color Finesse (included with AE), or Red Giant Software's Magic Bullet Colorista II.
I generally prefer to grade in a dedicated color tool (I use Resolve), but when I do grade in context in AE, I generally prefer Colorista II.
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