05.02.2024 – CG process
Week 15 – CG Process: From Matchmove to Final Composite
Throughout the previous classes, delved into various stages of the CG production pipeline, including matchmove, clean-up, and color grading. Now, it’s time to integrate these processes to seamlessly composite CG elements into a video.
Key Processes:
- Matchmove:
- Undistort the original plate and analyze the scene using the CameraTracker node.
- Create cards to match on the trackers. For a detailed guide on matchmove, refer to my previous post: Matchmove.
- Clean-up:
- Remove specific objects or markers on the original plate using projection techniques.
- To lighten the script, render and reimport the cleaned-up plate (preferably in .exr format to avoid quality loss).
- Roto the plate if necessary. For more details on projection, check my previous post: Projection.
- Slap Comp:
- Before starting the compositing process, create a simple slap comp by merging CG on the cleaned-up plate. This aids in checking the before and after of your work.
- Compositing:
- Utilize render passes from 3D tools to composite CG onto the plate. For insights into AOVs and passes, as well as adjusting multipass and relighting, refer to my previous posts: AOVs and Passes and Adjusting Multipass and Relighting.
Additional Points for Natural Compositing:
- Match Color using a Grade Node:
- Whitepoint from the original source to neutralize white.
- Gain from BG source and Blackpoint from the original source to neutralize black.
- Lift from BG source.
- HueCorrect Node:
- Select color (Ctrl), adjust the curve, and add points on the curve (Ctrl+Alt).
- Toe Node:
- Select the shadow area from the BG plate to match black. For more options, use the BlacksMatch gizmo.
- MotionBlur3D:
- Create a motion channel using the camera.
- Apply the VectorBlur node with the motion channel. If possible, use motion vector channels rendered from 3D programs for more accuracy.
Finishing Touches and Quality Check (QC):
- Incorporate Aberration (Gizmo), Defocus, LightWrap, Grain nodes, etc.
- After composing everything, conduct a quality check (QC). Merge the original and final plate with the Difference operation.
- Utilize QCTechnical (Gizmo), SliceTool (Gizmo), and Colorspace nodes for thorough QC.