This may be old hat to some of you, but I only figured this out after I saw a post by slowtiger some time ago.
When you select the SCALE tool and you're about to SQUASH or STRETCH a layer, its sometimes a good idea to keep the object's volume - that is, however much you squash it ONE way, it should STRETCH out the OTHER way.
Hold ALT when you're squashing or stretching. This way, when you squash an object down, for example, it will stretch out horizontally the same amount as you squash it down.
That little trick with the ALT key saved me a lot of time. Just in case ya didn't know.
Maintaining volume with Squash and Stretch in AS.
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