Adobe AFTER EFFECTS CS3 PROFESSIONAL User Manual page 415

Offset effect
The Offset effect pans the image within a layer. Visual information pushed off one side of the image appears on the
opposite side. At Best quality, the offset is performed with subpixel precision.
The new position of the original image's center point.
Shift Center To
The effect's transparency. The result of the effect is blended with the original image, with the
Blend With Original
effect result composited on top. The higher you set this value, the less the effect affects the layer. For example, if you
set this value to 100%, the effect has no visible result on the layer; if you set this value to 0%, the original image doesn't
show through.
This effect works with 8-bpc and 16-bpc color.
Optics Compensation effect
Use the Optics Compensation effect to add or remove camera lens distortion. Elements composited with
mismatched lens distortion cause anomalies in the animation. For example, tracked objects in a distorted scene don't
match the scene area because linear objects don't follow the distortion of the scene.
This effect works with 8-bpc, 16-bpc, and 32-bpc color.
The field of view (FOV) of the distorted footage. The FOV is relative to the size of the source layer
Field Of View (FOV)
and the selected FOV Orientation. The distortion amount is relative to FOV. There is no general rule as to what FOV
value applies to different lenses. Zooming in reduces the FOV, and zooming out increases it. Consequently, if footage
includes different zoom values, you'll need to animate the FOV value.
Reverses the lens distortion. For example, to remove wide-angle lens distortion, set Field Of
Reverse Lens Distortion
View to 40.0 and select Reverse Lens Distortion. Selecting Reverse Lens Distortion enables the Resize control.
The axis on which the Field Of View value is based. This setting is useful when matching computer-
FOV Orientation
generated elements to the rendered view angle.
Specifies an alternate center point of view. This setting is useful when using custom lenses that aren't
View Center
centered. However, in most cases, this control should be left untouched.
Maintains as much pixel information as possible through the distortion. When selected, FOV values
Optimal Pixels
are no longer reversible.
Resizes the layer when the applied distortion stretches the layer beyond its boundaries. To use this control,
Resize
first select Reverse Lens Distortion, and then choose an option. Off doesn't resize the layer. Max 2X resizes the layer
to a maximum of twice the original width and height. Max 4X resizes the layer to a maximum of four times the
original width and height. Unlimited resizes the layer as far as it is stretched. This option may require a large amount
of memory.
Add and match lens distortion with Optics Compensation
To match FOV values, layers must be the same size. However, if you select Resize, you can apply Optics Compen-
sation again and reverse the distortion using the same value (reversed). You can then apply another effect between
the two instances of Optics Compensation.
If you resize a layer using Optics Compensation and then precompose it into a larger composition, you cannot
reverse the distortion using the same value until you enlarge the precomposed layer to accommodate the expanded
layer.
1 Select the layer with the distortion, and choose Effect > Distort > Optics Compensation.
In the Effect Controls panel, adjust the FOV until a distorted edge or line appears straight. Note the FOV value.
2
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