Adobe After Effects - Manual (Page 186)

Lock To Zoom
Note:
Aperture
Note:
F-Stop
Blur Level
Film Size
Focal Length
Units
Measure Film Size
Note:
Link Focus Distance to Point of Interest
Link Focus Distance to Layer
Set Focus Distance to Layer
Makes the Focus Distance value match the Zoom value.
If you change the settings of the Zoom or Focus Distance options in the Timeline panel, the Focus Distance value becomes unlocked from
the Zoom value. If you need to change the values and want the values to remain locked, then use the Camera Settings dialog box instead of the
Timeline panel. Alternatively, you can add an expression to the Focus Distance property in the Timeline panel: Select the Focus Distance property,
and choose Animation > Add Expression; then drag the expression pick whip to the Zoom property. (See
Expression basics .)
The size of the lens opening. The Aperture setting also affects the depth of field—increasing the aperture increases the depth of field
blur. When you modify Aperture, the values for F-Stop change to match it.
In a real camera, increasing the aperture also allows in more light, which affects exposure. Like most 3D compositing and animation
applications, After Effects ignores this result of the change in aperture values
Represents the ratio of the focal length to aperture. Most cameras specify aperture size using the f-stop measurement; thus, many
photographers prefer to set the aperture size in f-stop units. When you modify F-Stop, Aperture changes to match it.
The amount of depth-of-field blur in an image. A setting of 100% creates a natural blur as dictated by the camera settings. Lower
values reduce the blur.
The size of the exposed area of film, which is directly related to the composition size. When you modify Film Size, the Zoom value
changes to match the perspective of a real camera.
The distance from the film plane to the camera lens. In After Effects, the position of the camera represents the center of the lens.
When you modify Focal Length, the Zoom value changes to match the perspective of a real camera. In addition, the Preset, Angle Of View, and
Aperture values change accordingly.
The units of measurement in which the camera setting values are expressed.
The dimensions used to depict the film size.
For best results, work in 32-bpc with Linearize Working Space selected in the project settings. (see Camera Lens Blur effect (CS5.5). )
Camera Commands (CS5.5)
After Effects CS5.5 and later has camera commands that can be used separately or with the Create Stereo 3D Rig function. To use the camera
commands, select a camera layer, and then choose Layer > Camera.
Creates an expression on the selected camera layer’s Focus Distance property, setting the property’s
value to the distance between the camera and its point of interest.
Creates an expression on the selected camera layer’s Focus Distance property to be the distance between the
camera’s position and another layer. This method allows the focus to follow the other layer automatically.
Sets the value of the Focus Distance property at the current time to the distance at the current time between the
camera and the selected layer.
Online resources about cameras
For a video tutorial that shows how to create and modify a camera and use the Camera tools, see the Adobe website .
Dale Bradshaw provides a script and sample project for automating the rigging of a camera on the Creative Workflow Hacks website .
Mark Christiansen provides tips and detailed techniques for working with cameras in the “Virtual Cinematography in After Effects” chapter of After
Effects Studio Techniques on the Peachpit Press website. This chapter includes information about matching lens distortion, performing camera
moves, performing camera projection (camera mapping), using rack focus, creating boke blur, using grain, and choosing a frame rate to match
your story-telling.
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