Jack Smyth, Car Colour Correction, DD1410, Visual Effects 1, Jamie Scott

To start off this Car Colour Correction, the first step the compositor took was to bring both of the images that are needed for the final product, into Nuke:

 

The two images the compositor is going to combine in this shot, is of this car, and the background in which they will be placing it into.

The first step taken toward this product is to actually make a rotoscope of the car in the foreground image.  These next few pictures will illustrate the different rotoscopes used to make a full rotoscope around the car, as well as any additional parts that may have been added to increase the realism of the final product.

 Below is an image of the properties box of the car roto, before the beziers were created. The compositor has set the output and premultiply to the alpha, this means that they will be able to see the whole of the shot while they are rotoscoping, instead of if the 'Output' was placed to 'RGBA', in which the compositors roto would be filled in with white.

 The rotoscope below shows the first rotoscope of the car, in particular, the main body. The two shots show the main body as it would look on the properties above, and also how it would look with the 'premultiply' set to 'all'.

Once the preliminary rotoscopes of the car have been finished, the car looks like this in the shot:

More rotoscoping was added by the compositor for the sake of adding in the realism of the underside of the car. To do this, they made a rotoscope around the bottom of the car, and then used the 'feather' tool, to drag out the sharp light that was underneath the car, this would lengthen the shadows and dim them a bit, which would help in the crossover shot when the car is to be colour corrected to the background. What is shown beneath this is the different beziers used to make up the entire rotoscope, each named:

It is now time to bring in a transform node, and a merge, to bring the car into the background shot.

The transform node works by allowing the compositor to move the entire rotoscoped car around in the background shot, and the merge is the tool used to actually bring the car into the background shot itself:

The merge node is used by the compositor by using two 'pipes', the two black lines shown connected to the transform node and the 'read4' background shot.  The pipes labelled 'A' and 'B' show which is placed where in the merge. This merge is an 'over' merge, meaning that one image goes over the next, so the car is linked in as 'A' which is the foreground, and the background shot is linked in as 'B' placing it in the background. This allows the rotoscoped car to sit in front of the 'read4' background shot.

The compositor in the image above has also placed the car to where they wanted it placed in the shot, and this is it's own process, because if the car was on the raised tarmac, it would look out of place, as if the wheels shown to the person looking at the shot were levitating.

After the car has been placed, the next step is the colour correction itself.  The first colour correct used in the shot is a colour correct to the background itself. What has been done to the shot through the colour correction, is to bring out certain colours, or light. The compositor decided to brighten and colour correct the picture to bring out certain areas of the shot more sharply, so that when a grade node is brought in, the shot would be darkened better than if the colour correct was not placed in, for the fact that some areas may be darker than others, and in using the colour correct, they have been balanced out for the shot:

Although these changes seem minor,  when the colour correct and grading for the car are brought in by the compositor, it changes how the image looks. The car itself has very sharp colouring, it is bright and is a bright colour of blue. The colour correct for the car is used to darken the car, so that it will match the background, but also match how the light in the sky would play against the car itself, how it might change how it looks, and how the environment will effect the colour.

The compositor chose to bring down the saturation, gamma and gain on the car first, to bring down the high colouration the car gave off first, which was sharp and bright. In the midtones the majority of the bars were brought back to darken the cars midtone of colouration. The highlights on this car were found where the sunlight in the first shot hit the car, which predominantly is on the bonnet of the car. The saturation and gain were both raised to balance the highlights out so they were not too strong, and so that the car would be given an overall darkness to it's colouring.

The grade for the car is used to darken the remaining colours off, such as the blacks, the sharp highlights and the shadow beneath the car and around the wheels:

With the car and the background colour corrected and graded, the final parts given to finish the product off, was to rotoscope out the windows of the car, and possibly use a blur tool, even very minor, to give it more realism, for when a picture is taken, objects usually have a small amount of blur due to focus.

For the windows, the rotoscoping tool called the 'Reveal tool' was used. This works by taking revealing the background shot through the parts revealed in the foreground, in this shots case, the windows. The compositor has revealed the windows so that the background would be shown through them, but to add back in the glossy look windows have, the output was placed from 'all' to 'alpha', which uses the window brightness from the original foreground picture, using this, the compositor has been able to show the background image through the windows, but keep in the look the window glass may have:

The final composite of the shot the compositor combined and colour corrected shows the overall shot, having the car placed in the bottom left of the screen on the road colour corrected to suit the darkness of the background image, have its windows of the car show the background and also assembling these tools, shown as 'nodes' into a nodal tree, that shows the foreground and background image with their corresponding colour corrects, rotoscopes and blurs:

Brief 01 Altar Sequence, 001 - 449, - Starting Roto work.

To start off this Rotoscoping, the option chosen in this first shot, was to Roto using Bezier curves, the Ornate lamp.

In the screenshot below, you can see how this starting roto has been made, with the Roto work being placed into two folders for that Roto node.

The 'Knobs_on_lamp' folder, encompass the detail on top of the Ornate lamp, making it far easier to manipulate the specific parts of this lamp, for instance, the more detail placed in this Roto node, the more you can utilize the different parts of the lamp. What if the person using the shot did not want the 'Knobs' to be there, this extra Roto work, though not entirely hard to do, may come in handy for adjustments to whomever this Roto work will be given too.

The process for the dragon on the side was similar, as you can see this was split into two folders in the same Roto node. There is a Roto for the top and the bottom, as well as the inside of the tail on the bottom, and the dragons beard on the top.  This Roto work means the person using this nuke has a detailed Roto to work with, in which the visual effect they wish to use may work more effectively, and if they seek to see the Roto work, the naming is clear on the folders and individual Beziers (Apart from the single one labelled 'Bezier1' which was edited at a later date).

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The next shot for the Roto focus was of the girl staring into the sky. In this shot, the Roto outlined the girl,:

From here, the Screen colour tool was used to find the cleanest part of the blue, which would then cancel out the colour surrounding her:

This shows the outcome of the screen colour, you see the girl, but hardly any other colour whatsoever around her, there is only the spill of natural light on her, so the an outer keylight was used to make sure that the Roto and Keylight are at least set in place, so they can be edited at a later time.

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 Finally, during this started Roto work came the shots of the children, the Ornate lamps, and the dragons. The first thing done to this shot was the hold out mattes for the overall shot, and after encircling the entirety of what was needed, the same process as above was applied to this shot, with the screen colour, and play with the screen matting tools such as 'Dilate'.

Once this basic hold outte matte was made alongside the similar keylights as in the previous shot, the Dragons and the Ornate lamp were Roto'd out using bezier curves, a folder for each dragon and one for the Ornate Lamp. After review of the other shots this was made in, the circles and blue-screen showing inside the lamp was also Roto'd out.