Visual effects research blogs
For my own project I will be
using final cut pro to convert the video footage into a series of images which
can then be used in Match mover to track. Once I have the images tracked
properly I will be using Maya to animate in. the next step would be to take my
MAYA file and use Composite to make sure the lighting and animation match the
video footage. If this goes well I can the put the file into after effects to
enhance the final video.
There is
lots of different software available for the various different steps in visual
effects. For tracking footage there is Syntheyes, Nuke, After effects and Mocha
Pro. One of the features that stood out
with Mocha pro was that it had a tool called Remove module. With this tool you
can get rid of unwanted tattoos or other elements. The software that was least
recommended for tracking was After effects. Apparently it works well for 2d
footage but when it comes to 3d the tracking is automatic, takes a long time
and also may not work as well when the video needs refining.
For
compositing the software that came up the most online were After effects, Nuke,
Autodesk combustion, Flame and Eyon Fusion. The software that was ranked the
best for motion graphics and Compositing was After effects. Although you cannot
model or animate in 3d using this program, there are many different import and
export options that allow to easily embed camera movements, lights and
different passes which can be used for further compositing. The software that
ranked the lowest was Autodesk Combustion. This software has apparently not
been updated since around 2008. It is also a professional node based program,
however it is not a common program to use (unlike After effects and nuke) so
therefor there are few resources and training videos available online.
After creating a story or idea,
the next step in Visual effects is to film footage. When shooting footage you
have to make sure that the camera movements are as smooth as possible so that
the video can be tracked properly. There are lots of different camera angles
that can be used, for example: Dolly zoom, Long shot, deep focus, Matte shot,
Pan, tracking shot and Steady cam shot. When making my own visual effects I
will be using a zoom to do a close up of my desk and a tracking shot to follow
my object around my room.
The next process is match
moving. This is where a program like match motion is used to recreate the live
action camera movement so that it can be used in a 3D animation program. This
is important to get right as you use this track to make sure your animation is
matched up correctly so that when it is put with the live action shot, they
will both be perfectly in sync.
Once
the camera track is imported into a program like Maya, you can animate the 3D
elements. When modelling/animating one key factor that you need to get right is
the lighting. the more consistent the lighting is in the footage that you film,
the easier it will be to recreate in Maya. Taking this into consideration, I decided to
do my animation inside as it would be easier to recreate. When you film footage
outside the natural light can change depending on several factors such as the
weather and shadows. When adding lighting in Maya you need to keep in mind the
natural light that is given off my certain surfaces as well as an ambient
lighting. there are many different types of lights in Maya that can be used to
simulate the natural light from the video footage. For example: ambient, area,
directional and volumetric lights. Ambient light is a widely distributed light
that bounces off objects in the scene. Area lights can produce higher quality
light and shadows but can take longer to render so it’s best to use them for
still images. Directional lights are lights that will hit a set of objects from
the same direction and will cause the shadow to also stretch in the same
direction. Directional lighting doesn’t stay to one local area so they work
best as secondary lightings. You can change the different settings of these
lights as well as the colours to make them look as natural as possible. You can
also tweak the colour, intensity and spread of shadows. In my animation I will
be using directional lighting as a secondary source and ambient lighting. the directional
lighting I will use to try and simulate the natural sunlight coming into my room,
and the ambient light I will use to create shadows and illuminate the room
better.
When rendering the animation or
image, you can render the different layers or passes. The main pass that is the
full colour render is called a beauty pass. This also includes diffuse
illumination, colour and colour maps. It does not include highlights shadows
and reflections. There is also a shadow pass which renders out the shadows.
This normally looks like a black background with a white highlight where the
shadow will be. Lighting passes can be rendered out as multiple layers and can
be used instead of a beauty pass. The lighting pass will create different
layers for the different lights in the scene. Other passes include reflection,
Depth and an effects pass.
After the different layers are
rendered out, you can then put them all together. This stage is called
compositing. A common way of compositing over live footage is by green
screening. This Is where a green screen is put behind the live action footage
and then is replaced by either digitally made content, or different live action
footage. When making my animation, the compositing stage will consist of
putting together my animated work from Maya and the live action footage from my
room. I then plan to put my final image into a program like after effects to
clean it up and enhance some of the features.
I started to look at different examples of visual effects
and how they were created. The first one I looked at was a sequence from one of
the Diehard movies.
Before watching this I didn’t know that so many elements of
the final video were created in 3d. although some of the elements were already visible,
they were modelled in 3d so that the effects (breaking through the wall) could
be added. I also didn’t realize that there were so many different layers of
footage. It shows how different elements, for example the buildings in the
background are added in separately. You
can also see the different layers of lighting that are added to each of the
different modelled elements, and how they are built up. I think that this is
going to be one of the hardest things to match when making my own visual
effects piece.
In this video, it broke down the different layers and stages
in the making of the film Big Miracle
Even though there was clearly a lot a detail put into the modelling,
texturing and animation of the whales, they still do not look very realistic in
my opinion. In the Die hard footage everything was very realistic and I thought
that some of the 3d models were actual parts of the live action footage,
however in this example I can tell that they are animated. However the elements
that have been made using the green screening method I think have worked really
well.
https://www.youtube.com/watch?v=g7F5w4NChUE
I really like the way this video was put together. The
movement of the butterflies looks really natural. After watching this example I
have decided to use a butterfly in my own work instead of my previous two
ideas. The background image itself does not change, and there were different
light effects and mist added. I have managed to create mist in After effects
before which leads me to believe this video was composited in after effects. One
of the things I would change about the effects is the rays of light that appear
the same on all of the trees that are towards the front of the image. If the
trees were put on different layers then you could have the light look different
in each area. Another thing that I would change is to use a better quality
image as the backdrop. In some parts of the animation they go a bit blurry. In
the video footage that I captured for my own work I have a lot of light coming
in through a door, so I think It would look nice to experiment with the rays of
light.
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