After building the whole environment, This week I focus on CG Integration, including flag integration, reflection, and 2D effects of the obelisk

My Responsibility for Week 7 (shot 1& shot 4)
Fog Refinement (Fixing Hair Issue)
New Obelisk Testing
2D Effects of the Obelisk
Flag Integration
Roto Refinement
1. Fog Refinement
The foreground fog created last week seems to crush the black level of the image a lot, turning the whole scene grey. In this case, I remove the foreground fog and refine the background fog to improve the contrast of the scene.
Fog adjustment before & after
To increase the density of the fog, I use a grade node to add contrast to the alpha channel and also use a grade node to whiten the bright part of the fog

After increasing the density of the fog, the hair edge becomes an issue. Previously I separate the actor as a single mask to color-correct it. So the layer from back to front gonna be like this: raw footage - sky footage - fog - person
Since the person is still a rough key that can not have clear and shaped edges. When the fog merged in between, the edge of the person largely relies on the edge of raw footage. In this case, I need to sharpen the hair edge of the person's key with the Keymix node and roughly roto the head part.

Fix hair issues before & after
2. Obelisk Reflection Testing
I got five layers for the obelisk, beauty, shadow, reflection, reflection mask, and shadow projection. I test the five layers from the range of 600 to 700.

The beauty, shadow, reflection, and reflection mask work great, but the shadow projection is a bit off. The projection was a plane put in front of the obelisk in Maya. The plane has the black and white mask of the person that I exported from Nuke.
3. 2D Effects of the Obelisk
Effects are usually the most expensive part of the CGI workflow, but Nuke is such a powerful tool that can apply some 2D&3D effects by using some simple nodes. In order to give an effect for the main obelisk sign, I need to roto the sign shape first and project it onto a card in the 3D world.

Since the obelisk is CGI and the position is slightly different from the cube (which represents the position of the obelisk when doing 3D tracking) in Nuke, the hardest part might be finding the accurate position of the card, and adjusting the size to match the sign. Once the position is right, I give it glow effects by using node Glow and VolumeRays, the effects will stick with the track of the CG sign, after that, I only need to add keyframes to the effects.

4. Flag Integration
The flag I got from my teammate

I denoise the flag first, blur it for the close-up shot, and make it clear when it turns into the long establishing shot. I also add the light wrap node for the actor to help the hair blend better with the flag background.
Nodes for the flag Integration

4. Roto Refinement
After applying fog to the background, the missing part of the person key becomes more obvious, so I need to refine some roto for it. Since the person keeps moving, adding keys frame by frame is not good when the shot plays, so I track his necklace to Matchmove the roto

Roto Matchmove before & after
The Next Step
Flag reflection
New obelisk for all frame
Face-cracking fade effects
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