Task 1 – Spiderman
I began this task by setting out my background plate in Nuke, in this case it was the footage of Spiderman running up to a wall and doing a flip inside what looks to be a gymnasium.
I set up the background with a keylight using the Spiderman plate as the ‘source’. I then included a Roto node, and connected the ‘bg’ pipe to the Spiderman plate as this is the one I was wanting to modify, whilst also connecting the ‘OutM’ pipe from the roto to the Keylight. 
After setting this up, I then selected my Roto node and used the bezier tool to outline the body of Spiderman into different parts. I started with the head, and worked my way through each frame to edit the points of the roto to match those of my subject. Staying precise to theb point became difficult due to heavy blur in the original footage, however, using the feather setting on the roto helped maintain the quality throughout.
After finishing the roto, I checked my progress by changing the keylight settings to ‘inverted alpha’ this allowed me to see exaclty what was happening inside the roto and give me a clear picture to how my roto work had progressed.
After this, I thought it was best to connect the background that I was wanting to implement my subject onto, as seeing them together would help me notice any problems with lighting between the two and scale. To do so I needed to reformat my background image as it was different to that of the Spiderman’s.
Following my keylight, I added a motion blur to my subject, as doing so created a more visually pleasing output. I then also used a ColourCorrect node to slightly edit my Spiderman to look more custom to the scene. I lowered my contrast and saturation as I thought they were too bold for my chosen background and it’s lighting. and also transformed the position of my subject to make sure it looked appropriate regarding the background. 
I also animated the position of my subject throughout my footage, as when played back, it was noticed that Spiderman’s foot had broken the perspective and looked like it had gone inside of the pavement in my background. I fixed this by translating my subject up to when he takes a step, this gave the illusion that he had gained altitude whilst running onto the pavement which helped the footage look more realistic.
After watching it back I decided that I wanted to add a shadow to increase the reality of my video, and the easiest way to do this was to replicate the roto that I had used for the original Spiderman plate, and skew and translate it. I needed to make sure that whenever the original Spiderman’s feet touched the ground, the feet from the shadow of Spiderman came into contact with the original. 
This however became a problem when the Spiderman flips off from the wall, as the shadow distorts from the perpective and ruins the whole look of my video. This meant that I had to animate the translation of my shadow to fit the scene. I animated the skew settings, the rotate and the transform attributes to make sure that the end result replicated that of reality.
My finished node tree was neat and tidy with the use of dot nodes to ensure the nodes did not become tangled or overlapped.
Task 2 – SkyDiver
As with the Spiderman task, I began by inserting my footage of the Skydiver, in this case he was on a box in a blue screen set up.
I then started my roto just as I did with the Spiderman project. However, instead of going through frame by frame to change the points of the roto; this time I created a roto for each different shade of blue thast there was on the background.
I did this as I was intending to use a keylight to select that blue colour and get rid of it, meaning that I would be left with my subject.
Here is the set up of my keylight and rotos that came from the Skydiver footage.
As explained, each of these roto/keylight’ s contains a different colour of blue that I am wanting to erase from the background.
I selected these shades of blue by going into the keylight node, selecting the colour picker and clicking ‘ctrl’+’shift’ to create the target to where I was wanting to select. I then could check how well each keylight was working by changing its OutM Component to inverted alpha, when changed, it shows a higher contrast between the colour that is being taken away (black) and the colours that are left intact (white).
At points where my rotos were showing too much grey, meaning that is was a poorly executed keylight, I changed this by upping the screen gain, so that the greys would fade back to black. The only problem with this is that often I lost some detail if I pushed the gain too far. 
After making sure each of my keylights were working correctly with my colourpicker selections, I combined them together using an AddMix node. Making sure thast for each of these nodes I had inserted, I had set them as pipe ‘b’ so that they would add over the pipe ‘a’. 
Once this had been fully set up and structured using the dot nodes, I then incorporated my next node which was a camera shake. This helped to ensure that my video seemed as thought it had been filmed by another Skydiver that had taken the footage whilst following the first subject. My next addition was the plate that contained the picture of the ground, I had animated this using the transform node as I wanted to follow the impression that the Skydiver was falling so I had to increase the scale very slightly throughout the video.
I then wanted to create different layers on the clouds so I went back up the pipeline to put them in where I wanted them situated. Giving them differernt ColourCorrect properties and giving one layer a camera shake really improved the reality of my video as the more layers that I had added came the better the illusion of realism.
I made sure that there were different settings for each camera shake, where the clouds that wre closest to the SkyDiver had the larger intensity of shake compared to my Ground plate that had the least amount of intensity. This helped to improve the perspective within my footage with greatened the effect of the video being real.
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