Apple Shake 4 - Manual (Page 211)

Chapter 6 Importing Video and Anamorphic Film 211
The only speed hit is in the interactivity to adjust the viewed frame. This is the
parameter you should use when dealing with video clips, since you change the X axis
and leave the Y axis, which contains the sensitive field information, alone.
• Film: With film media, you should set the proxyRatio (in the useProxy subtree of the
Globals tab) to .5 (1/2). Use of the proxy system reduces your render time for
interactive tests by half. Unlike viewerAspectRatio, this procedure halves the Y value,
rather than doubling the X value. However, the proxy system affects your output files,
so be sure to set the proxyRatio back to 1 when you render your images to disk.
Remember, you want to send squeezed files to the film recorder.
Following the above guidelines for this anamorphic film plate, open the useProxy
subtree and enter a proxyRatio of .5 to correct the squeezed element.
Node Aspect Ratio and the defaultAspect Parameter
Certain functions need to be aware of the current aspect ratio—specifically functions
dealing with circles or rotation. For example, if you apply a Rotate node to an
anamorphic plate, the image is distorted.