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How Can You Use Rotoscoping to Transform VFX Results

Rotoscoping is the Holy Grail for any VFX artist looking to make it big in the industry. It refers to the most critical process in the visual effects as you can trace over live-action footage, frame by frame.

The technique breaks a shot into individual layers to animate the properties separately and add extra assets for unlimited creativity. Rotoscoping VFX can create a mask or matte effect for a visual element to extract it and place it on a different background.

The element can be masked to change the colors or other details, and you can transform your VFX process to create a fantastic animation. Here’s how it works:

Understanding Rotoscoping in VFX 

With advanced technological solutions, you can find a set of tools in your compositing software to rotoscope any animation. The tools help create new alpha channels for different parts of a video or image sequence.

Since the footage is directly taken from the camera, it has no alpha data, and the artists have to create it by tracing over specific elements manually. You can create varied shapes around an element or object in the video and animate them to match each frame’s movement.

According to the complexity level, rotoscoping may take a few hours or days to complete the footage. Blue and green screens simplify the process of compositing, but it can’t apply to every shot. Hence, rotoscoping is essential to utilize visual effects for incredible results.

You can make the most of this technique by following these best practices.

Avoid Starting with Matte

If you want to excel in your rotoscoping VFX results, start with keyframes. Many VFX artists are tempted to draw a matte first, but it doesn’t always work chronologically. Since rotoscoping is an advanced form of animation, you can apply traditional principles of using keyframes to deliver excellent results.

Keyframes contain the most appealing and dramatic movements or shots. You can start by drawing the keyframes and move on to smooth the motion with in-between elements.

After drawing the keyframe mattes, refine every element in each interval, and repeat the process until you get the desired effects. This way, you can maintain consistency in the matte by adhering to the element motion. Also, it reduces extra work if you use automated interpolation between keyframes.

Use Minimum Points

Your footage has at least 24 mattes that can increase the probability of inconsistencies if you add more points to it. Though you may want to start your footage with maximum points to outline the element, try to keep it to the minimum and use only the essential points for tracing the subject.

If you change the outline over different frames, the result will have jittery effects, and you can’t even trace it back to the relevant point. Now, please return to your keyframes as they contain the most challenging shapes.

Here, you can create minimal matte points and move these points in groups to control the shape. Using advanced compositing software with several rotoscoping VFX tools can help in curve manipulation with minimum points.

Use Different Shapes

Sometimes, an object can be complicated in its shape, and you can’t use a standard shape for the entire subject. In this case, you can separate different parts of the object in sub-shapes.

For example, if you are rotoscoping a person, you can separate the hands, forearms, and fingers to move them independently. It is quite challenging to follow the outline in a complex movement involving two or more characters. You can do so efficiently by using different outlines.

Use Minimum Keyframes

When animating a rotoscope along with the elements and their movements, don’t create separate keyframes. If you use the right software, your computer will automatically interpolate different keyframes.

It is similar to the process where an animator draws key poses. You can also choose frames with maximum movement and adjust the shapes.

Don’t Forget the Principles

When you are creating keyframes and animation subjects, rotoscoping looks similar to animation. Hence, you can apply the time-honored principles of animation to ease in and out of the footage. With this in mind, you can easily figure out each subject’s movements and put your keyframes in the best spots.

Another essential principle to follow is to study the footage before getting started. Look at the various directions, subject parts obscured by other elements, camera shakes that need adjustments, etc. If you know your footage, you can make a better timeframe for the project and work like a pro.

Rotoscoping is one of the most critical techniques in VFX. So, if you want to deliver the best results in every film or animation you make, work with diligent and skilled rotoscoping artists.

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