Chromanator Tutorials: Grading & Effects
Lighting can often be the crucial factor that either completes a composite or ruins it. When combining several effects with live action, special care has to be taken to match lighting between all the elements, otherwise the seams will become worryingly obvious. Chromanator's grading tools can help to augment the original lighting and blend everything together.
For this example I'll use a relatively simple lightsword scene and demonstrate how Chromanator can be used to enhance the lighting,
The live action plate looks like this:
Using AlamDV, the lightsword effects are easily created and exported on black:
Using the Add composite mode (available in a timeline object's Properties dialog, accessible from its menu), the lightsword can be easily composited onto the live action:
As you can see, the lightsword effects include a clash for when the two blades connect. However, the illusion is somewhat dampened due to the clash failing to cast any light on the surroundings. This is where the grading tools become useful.
First I place another copy of the live action clip between the lightsword effects and the main clip:
The second clip will be where we provide the lighting enhancements. If I were changing the lighting of the whole shot I could just do it to the original clip, of course. But for this example I'll be a little more specific.
I need to alter the second clip's lighting, so I select it and switch to the Object View, then go to the Grading toolset.
The obvious choice is to use the brightness tool, but this tends to wash-out the picture and lack impact:
Instead, I want to use the Super Contrast tool, which enables close manipulation of the light and dark areas of the image.
- Raising the black point darkens the shadowy areas of the shot.
- Lowering the white point brightens the light areas of the shot.
By lowering the white point to 147 and raising the black to 42, a very dramatic increase in light can be achieved, whilst retaining and deepening the shadows:
However, in this instance I don't want the lighting to effect the entire set, so I'll add a quick garbage matte:
The garbage matte is carefully drawn in a shape to highlight the areas that should be illuminated by the lightsword clash.
- The garbage matte needs to be inverted, so that everything except the selected area is removed.
As there is an identical clip directly underneath, the areas removed by the garbage matte will still appear to be there, whilst the middle clip contains the graded version. This is the result:
As you can see, the three clips are composited together so that it appears that the live action clip has a bright area in the middle. Of course, the bright area still has a rather obvious edge.
- Adding a feather of 60 to the garbage matte blurs the edges, giving a natural appearance to the artificial lighting.
Compared to the original composite, this version is far more dynamic and convincing, creating the illusion that the lightswords are actively affecting the surrounding lighting.
Click here to watch the clip in action.