Visual effects are the effects achieved and created outside of what is shot – they are all made in post – production, added in by computer images.
Digital Compositing - 0.59 - 1.17 Digital compositing is the process of layering effects and images over each other to make a final image. It can be really useful if the company making the film doesn’t have the money to use actual effects on set.
Digital Compositing is used here to add in effects like the fire and smoke coming off the boat and the helicopter flying overhead. This was done with green screen and digital composting because it would've been very expensive to have a fire on a cruise liner and then get helicopters and proper fire equipment out so its easier to do it in post and add in all those effects.
CGI - 0.05 onwards CGI stands for computer generated imagery, it is the addition of separate computer graphics to create something that wasn’t there before.
CGI is used in Avatar because obviously there isn't a separate land with aliens that they can film in so the production team have to make them another way. Potentially, the makers of the movie could've used make up to create the effect of the alien form however that would take so long and it wouldn't have the same realistic effect.
Matte Paintings - 9.03 onwards A matte painting is a painted landscape, building or effect which allows filmmakers to have something in shot which is not actually there. This was used many years ago as there wasn’t the luxury of a green screen and CGI to make the scene come alive. Artists working in matte paintings had to have a great knowledge of perspective to make the shot seem realistic.
In the shot with the castle, the director used matte paintings to create the castle because it would've cost a lot of money to shoot at a real one so it is easier to create it later on.
Morphing - 0.59 - 1.22 To morph something is to change smoothly from one image to another by small gradual steps using computer animation techniques.
Morphing is used in this scene because the movie needs the morph to make the characters make sense, so this girl has the power to morph into people but if she just stuck on a mask, it wouldn't have the same effect and the film wouldn't make sense.
Rotoscoping - 6.36 - 7.12 Rotoscoping is an animation technique used by animators to trace over motion picture footage, frame by frame, when realistic action is required
Rotoscoping is used for the lightsaber effects in Star Wars because the beam from the lightsaber is constant and has to follow the handle. For this to work as well as it did, rotoscopers had to go into each frame and draw the line of the lightsaber wherever it was.
3D Animation Animating objects that appear in a three-dimensional space, they can be rotated and moved like real objects.
Toy Story was the first digitally animated movie so was a really big development in the animation world, the filmmakers used 3D animation because its more fluid and looks more 'realistic' in its own world because everything is the same, the toys and the humans.
P2: Special Effect Techniques
An effect created on the day of the shoot, like explosions or props. They are used because having real explosions or real smashing glass looks better and more realistic than say CGI created or something put in later. It is also better for the actors as they actually have something to react to.
Mechanised Props (Animatronics) Mechanised Props or animatronics are props that have some sort of movement programmed in, so can maybe shake, do an action or become an actual character. They could be robots, or just something simple, like a moving table.
The sorting hat was made as a mechanised prop because it gives more of a realistic feel because you can actually place the hat on someones head as oppose to maybe a CGI hat that wouldn't look as good.
Stunt Props (sugar glass) - 0.24 - 0.30 Stunt props are things on set that look realistic but are actually fake, there are a range of stunt props from sugar-glass (made to look like actual glass when smashed but doesn’t actually hurt or something like a fake gun. Things like fake guns are good because it is something that the actors can react to which won’t actually hurt them.
The sugar glass in this shot is good because it makes the effect more realistic, if it was done with something like CGI or if the dude just punched him, the effect wouldn't look as crazy or out of order.
Scale Models Are models of things needed in the movie like locations or roots, machines and the like. These are shot wide in frame with a backdrop making it seem bigger and the size they would be in the world of the movie. This is good because it saves a lot of money because instead of making the prop full size which would cost millions its just a small model.
Making a scale model of Hogwarts is better than using real footage because its always the same, if you tried to make hogwarts out of other castles or buildings, it wouldn't look like one fluid piece. Also with the scale model, you can video nice flyovers and establishing shots, you can also make the castle in any weather at all or at night or day - the options are limited. I found a tour of the scale model they used that shows the scale of how big the model is.
Make up/Prosthetics 0.35 - 0.51 Prosthetics is just enhanced effects of make up using materials like silicone to build up different layers on the face and create monsters, different creatures or wounds.
Make up and prosthetics were used to make mystique's blue form in the first men because the CGI they had then was not as developed as the CGI we have today. This meant that the filmmakers had to make the makeup as realistic as possible, as you can see there were lots of layers that built up to make the final product.
Pyrotechnics - First video - 14.29 - 14.40 Second Video - 4.00 - 4.30 Are controlled explosions or fires that is done on set. This makes the scene look more realistic, more than if the effect was done with something like CGI. Pyrotechnics require an expert on set that can set the explosions off with the upmost saftey.
The pyrotechnics in this scene enhance it because there is a clear repercussion of what Voldermort is doing with his wand. Unlike fake CGI explosions, You can actually see rubble and debris spilling out which is good because it gives the scene that realistic feel.