Sky Replacement
Objective:
To Replace the Sky in the footage and color correct it to match with the original.
Technique used:
Match Moving (3D)
Luminance extraction (Alpha Matte)
Color Correction
Original:
Challenges:
a) The camera rotates. The car's movement needs exclusion from the Tracker. For effective sky replacement, precise tracking is essential. The track's error value should be less than 7.
b) Many gaps exist between the tree branches. It's crucial to correctly extract the Alpha channel.
c) The light in the footage is coming from the right side. Choose the right image for replacement.
The Procedure:
I used the 3D CAMERA TRACKER with this ROTO data. This ROTO shape ensures that the moving car doesn't disrupt the 3D CAMERA TRACKER, giving an accurate camera solution for the video.
Once the camera is tracked i have created a 3D scene where i can see the track markers and place the background properly.
i have used reformat node to set the pixels of the footage according to the roject settings. Later i have used a keyer to remove the sky.
After the keyer removes the sky, residual dark spots may remain in the white space. To rectify this, I employed the roto node, a tool that meticulously distinguishes between black and white areas. By manually outlining and refining the edges, I ensured a precise separation, eliminating any unwanted artifacts.
This meticulous process guarantees a clean and seamless transition between the foreground and background, enhancing the overall quality of the composition. The roto node's capability to intricately define boundaries facilitates the creation of a visually polished final result, free from any distracting imperfections.
once the roto node is used to premult is used to multiply alpha matt and RGB.
After all these process i have placed a sky footage to the background where the footage is reformatted according to the project settings. Here i have created a card so that the frae is place on the card and displayed in the background.
Afterward, I utilized the TimeClip feature to shorten the footage, ensuring optimal duration. Additionally, I incorporated a Frame Hold node to preserve a specific frame consistently throughout the footage. This strategic implementation maintains visual continuity and emphasizes crucial moments within the sequence. By effectively managing timing and frame selection, I enhanced the overall coherence and impact of the edited content.
Final Output:
