Trying to do some very accurate reshapes, and for the most part everything works as one would expect at quarter or half resolution. But as soon as you go to full rez, the "warp" gets quite an arc to it.
I have added more correspondence points but it's not really fixing the problem (and really there is no problem at the lower resolutions, so it's got something to do with full rez and not too-few correspondence points).
Note also in the image that there is a "leak" in the image at full rez (that would be fixed by a mask) but it's not needed at half rez.
And now that you mention it, I'll give it a whirl on the mac.
In playing around again I can get different results depending on whether or not I precomp the shot I'm reshaping. But it's obvious something is wrong - see image.
The green mask is the source and the yellow is the destination. Since the green encompasses the entire image, there should be nothing beyond the border of the yellow mask (except maybe a 1 pixel smear). But you can clearly see the entire right half of the image is being stretched beyond the edge of the frame (and the texture continues so it's not a smear).
Its almost as if some of the correspondence points are vectoring in the opposite direction.
(and yes I have done them in the same order).
It seems that image resolution and ratio vs comp ratio make a difference.
With an HD image reshaped within an HD comp, I'm having perfect results. But if you throw a larger image or an image that does not have the same ratio as the comp, then you get all sorts of different errors.
The closer you get to the comp size and ratio the smaller the errors are.
If the image is larger but the same ratio as the comp, just precomp the image and then do any scaling and reshaping in the smaller outer comp - I've had good results with this as well. Unfortunately this does not work if the image is larger and a different ratio.