Initial Scene Preparations

First thing's first. Well, actually, it is calculating lens distortion, removing grain and motion tracking and such.

Here are a few examples of my initial preparations for a shot and how this applies to the final touches of Sh040C:

When using lens distortion, there are a few techniques. I prefer using either of two options: Nuke can automatically calculate - in a similar fashion to tracking - the lens distortion. The other is drawing points along straight elements in the scene and that will calculate if these elements bend due to lens distortion. I first of all use the former and use the latter to test if the lines are straight. If this does not work, I opt for the latter and draw the points manually along the lines.

This is an example for the lens distortion process:

This is the footage with lens distortion from the camera.

I have now applied the 'image analysis' and drawn a line with 'line analysis' in order to check it is has worked and the straight lines are indeed straight. They are.

Looking at this line on top of the original lens distorted footage, you can see that there is now a gradual distance from the line in the corners of the frame. This clarifies that the lens distortion has worked.

It is also important to clean out any noise from your footage if you are going to composite anything into it which may have no or different types and levels of grain.

Here is an example of removing grain in this shot:

Looking again at the original footage there is obvious noise/grain.

For comparison, here is the image once the Denoise node has been applied to the footage.

After the compositing of undistorted and de-grained footage/elements, it is important to re-apply the lens distortion:

Before. Notice the distance between the image and the end of the frame at either side.

After. Notice that gap filled and the rest of distortion now visible.

After. Now all of the smoke (subtle) have the same lens distortion to the originally shot footage.

The lens distortion makes everything like it should again and fills the frame correctly, as well as draw attention to any elements in the framing which the director designed or the DoP chose to bring out in the shoot, along with the elements that have been composited (I believe that it is good to place things in the composite considering the later lens distortion to make sure it looks right.)

And, re-graining:

By sourcing a flat area of the original plate (such as the concrete), using the F_Regrain node, it gives me an idea of grain. But, it always seems to require changing the grain size and amount by looking at the original footage again to use the eye to match it as best as possible.

After.

This is my process so far, regarding the first few cases of using the very effective method.