Step 4)

Matchmoving the head to the body - With a stabilized, premultiplied fg head, I could now attach it to the headless body of the bg. I typically like to view my progress interactively, so I'll temporarily plug the fg and bg into an Over node while I work. For the body track, I found a reference point at the base of the man's neck. I repo'd and scaled Steve's head to fit into place and matchmoved it to the man's body movement.

Step 5)

Color correction - Is one of the most important aspects of compositing and color correction in Shake is a science in itself. Aside from having a good eye for color matching, a thorough understanding of premultiplication and how it affects color and edges is another essential skill.

Since the fg head became premultiplied by setting Primatte's output to On Black, it needs to be unpremultiplied with an MDiv node so color adjustments can be made with optimal results.

SpillSuppress was then applied to remove blue spill and Mult (for color) and ContrastRGB (for blacks) were used to color correct Steve's head to fit with the bg. Mult and ContrastRGB are "concatenating" operators which collapse together into one function, allowing for more efficient processing and maintaining of color integrity. An MMult node is applied after the color operators to premultiply the fg again.

It is also worth noting that Betsy Paterson took advantage of Shake's custom macro capabilities and developed one to make the new footage color appear degraded to match the old footage. This macro was distributed to the compositing team so all the shots would look consistent.

Step 6)

Adding a cast shadow onto the face - The original plate had the woman casting a shadow onto the man's face (fig. 9). I wanted to do the same thing to Steve's face to give the impression that he really is in that environment. I used a simple Rotoshape which was blurred and plugged into a Brightness node to darken that area.

Blending hair blacks into the bg with a grad - The original plate also revealed to me that Ling's and the man's hair edges and blacks seemed to "melt" into the bg with no apparent seam. So, I created a roto along the inside of Steve's hair edge, blurred it and performed a boolean with a Layer node set to Inside to establish the grad matte

I took out a Color input node and sampled the dark bg color behind Steve and pumped that through a KeyMix along with the grad matte I just created. I dialed in the fg percent just slightly and Steve's hair blacks and edge blended into the bg nicely.