Lets start with the still piece, for this footage, the windows were achieved using rotos. As seen in the picture below this paragraph, the car was viewed in the new background and the windows were then roto'd around.
In the roto settings, the output was changed to none, and the premultiply to all, this means that when the footage is viewed, it will show the green fence and out-building rather than the grassy field.
After this various different nodes were used to make the windows look realistic, like an edgeblur, colour correct and a rotopaint (as shown below).
The shadow, was achieved through similar methods, first the shadow and the wheels were roto'd in the original car footage. The roto was then feathered to give the impression of the shadow fading away.
It was then merged into the new background and a transform node was used to place the shadow and the wheels in the right place. Finally, a colour correct node was read in to make the shadow look more realistic.
This is an effective method that works perfectly, but what about with the pan piece?
It turned out that the rotopaint node, that was used on the still piece, could be used to do the entire job of all the nodes listed in the picture above. The link to the blog post on the rotopaint node and how it was used in the car pan piece for the windows and shadow is below:
In hindsight, if this project were to be done again, the rotopaint node would probably be used for both pieces, because it can clearly do all the work in one node, that took six nodes to do on the still piece. The fact that so many nodes were used in the first place and then in later pieces they weren't, shows development in the skills of the compositor. Both of these methods do the exact same job and come out with the same results, but the rotopaint is easier and quicker. However, if the situation was different, e.g. one footage was night time and the other in the early afternoon, or if there was a particular light shining on the car and the glow needed to be replicated in the windows, then the roto method from the car still piece would be more effective because it can then be colour corrected and graded. Of course the roto node could simply be replaced be replaced with a rotopaint and then the colour correct node can be attached to it, but at the end of the day it is entirely down to the persons best judgement. It is the same story with the shadow, granted the rotopaint tool probably does look slightly better, but it depends on the colour of the background; the background for the still piece has been given a different colour correction than the the pan piece, which requires it the have a harsher shadow which can be achieved better with the roto and the colour correction nodes method. Possibly at a later stage the rotopaint tool will be tried on the still pieces shadow to see if it can provide a better end product.
No comments:
Post a Comment