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In the previous video, you saw different ways to use the colour correction tools in Autodesk Smoke.
We’ll now shift our focus to compositing with the Axis timeline FX tool.
In the sequence, you can have as many video tracks as you like to perform standard layer compositing.
Each video track can be considered as a layer, and you are looking from the top most track downwards.
To composite layers together, all you need to do
is add a new video track or use an existing one and edit your source clip onto the top layer.
Select the segment, right-click it and select add effect.
Choose the single-track compositor known as AXIS.
The basic parameters in the toolbar will give you quick scaling,
positioning and blending of the affected segment.
For more advanced controls, we’ll go into the advanced editor.
The first thing I am going to do is go to the bottom right of the screen
and reset all changes that I did in the basic parameters before entering the editor.
Secondly, I recommend that you enable the caching option from NO PREVIEW to PREVIEWFX.
For example, if this segment was stacked above 5 or 6 layers,
and the caching option was set to NO PREVIEW, the background would be black.
PREVIEWFX will process all layers underneath this current segment
and the result will be displayed as your background.
There are 3 main groups of parameters to the axis timeline FX – Object, lights and camera.
In this particular lesson, I’ll cover the object and lights menu.
Starting off with the object menu, the layout is divided into two sections.
From the middle to the left are the transformation controls.
This concerns object positioning in the viewer
From the middle of the screen to the right is the image and filtering controls.
Moving the object around the view can be done in 2 ways.
You can either drag the slider values for accurate pixel positioning.
Or you can set your cursor mode to MOVE through the pull-down menu
and adjust the on-screen widget to move the object in a gestural fashion.
MOVE is mapped to SHIFT+M as a keyboard shortcut.
There are two levels of transformation you can apply to an object.
There is the layer transformation and the Offset transformation.
Make sure you always use the layer transformation for your main 3D positioning.
The offset transformation is used when you have tracked or stabilized an image.
You’ll see this is a future video.
But for now, always ensure that LAYER is selected.
With the image controls, you have access to a pull-down menu with various blend modes.
You also have the ability to blur a surface, by dragging the slider.
You can also switch between common blur types.
Remember, Smoke is also a 3D compositing tool, where objects float in space in front of a virtual camera.
Your image is actually being textured onto a flat 3D surface that can be moved in a virtual environment.
So Smoke blends the world of 2D imagery and 3D compositing in various ways.
For example, you have 4 surface types you can choose from.
The default surface type is FLAT for a simple flat 3D surface,
like the one that is textured by the source clip.
The next type is Bilinear.
This 4-pointed surface is designed for corner pinning and 4 point tracking.
If you used corner pinning tools in other applications,
or Photoshop’s Distort tool, this will be familiar.
The third surface mode is bicubic that allows you to physically bend a surface in 3D space.
This will add true depth to your image, even if it was completely flat to start with.
The fourth and final surface mode is extended bicubic.
This has the same properties as bicubic, but you can divide your image
into further sections and manipulate them in any way you choose.
I’ve seen this used to create warping effects, fix camera distortion
and even align two locked off cameras.
In the future we will cover more advanced tutorials on these surface modes,
but for now we’ll stick with the flat surface.
Moving onto the Lights Menu.
In the Axis Timeline FX, you have a single light source,
which you turn on by pressing the Shading button.
Shading refers to an image’s surface, and how it reacts to lights.
This light can be moved around the viewer and it will only light the affected surface object.
You can use this light to create highlight passes
and you can also dial down the spread and the fall off to create a soft-edge spotlight.
A few more points on the axis editor.
To your right are the viewer navigation, animation and reset controls.
To the left of the screen are the render, preview, animation and viewer display controls,
to show the result as well as alpha channel or matte, of the selected segment.
If you exit back to the sequence, the changes applied in the axis editor
are also applied to the segment.
Before moving onto the next video, one other big topic I’d like to cover,
is the way an imported source’s alpha channel, is applied in a sequence.
I’ll navigate to the close up of the gladiator, where I would like to add a title.
You can create graphics and titles in Smoke but it’s common to be supplied with graphics
from outside of Smoke to composite with.
Let’s switch to the MediaHub to import a graphic made in another application.
Just a very quick recap, I’ll navigate to an image sequence with an embedded alpha channel.
Notice that the MediaHub shows me the image sequence as a clip,
which I can play back and mark if I want to.
In the general tab, change the Clip options, change the setting to CREATE MATTE CONTAINER.
This means that when I drag this image sequence into the media library,
the RGB and alpha channels will be contained in a single clip for easy access and keying.
It is very important to understand that Smoke will always treat the RGB channels
and the alpha channels separately.
With this option enabled, they are automatically turned into a container clip on import.
Or you have to do it manually in the sequence.
Returning to the Timeline TAB, I am going to edit the container clip over the background.
Notice that the alpha channel information is disregarded,
and the logo is not keying through the background.
Select the segment and add an axis Timeline FX.
This automatically turns on the Matte control, enabling the alpha channel’s transparency values.
The segment should now key through to the background.
In the next video, we will focus on some tracking and stabilising basics.