23.04.2024 – Copycat and Particle

Week 22 – Copycat and Particle

CopyCat: CopyCat is a Machine Learning node that allows artists to train their own network. The Inference node is the output of Copycat, and the idea is to work with images before and after, typically referred to as GroundTruth images.

How to use Copycat:

1. Use consistent frames to train Copycat.
2. Crop the area if necessary to reduce time consumption.
3. Apply Clamp, Log2Lin (with the operation set to lin2log), and remove all channels except RGB.
4. Ensure that the number of frames for the source and groundtruth images is the same to avoid errors.
5. Adjust the knobs in the Copycat node, including selecting the path directory to store the trained data. You can also adjust advanced settings like initial weights, model size (Medium or Large), batch size (leave it on Auto), and crop size (smaller crop for faster training).
6. If the result isn’t as expected, consider training it again with higher epochs or adding more frames for training.

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Particle: Nuke provides a Particle system that allows you to create various effects such as fog, snow, and more. The basic structure of the particle system includes several nodes:

• ParticleEmitter: This node is essential for creating particles. You can connect a 3D object to emit particles following its shape. Adjust parameters like particle size, velocity, life, color, etc., to customize the effect.
• ParticleGravity: Add gravity to your particle system by adjusting the y-axis. Negative values can make particles move upwards.
• ParticleDrag: Apply drag to gradually alter particle velocity over time.
• ParticleBounce: Make particles bounce off a 3D shape instead of passing through it.

• ParticleTurbulence: Apply noise to particle movement, dispersing particles in the x, y, and/or z directions.
• ParticleWind: Simulate wind blowing on particles by adjusting direction and velocity.
• ParticleVortex: Create a whirlpool effect by applying a circular force to particles.
• ParticleMotionAlign: Realign particles along their direction of motion for a more controlled effect.
• ParticleCurve: Apply a curve to particle properties (such as size or mass) to change them over time.

More information of particle: Particles Nodes (foundry.com)