I am trying to "square up" an image.  It is a scanned map which shows section lines 
representing a one mile square.  Because of the map projection, the section lines on 
the map aren't quite square (opposite sides aren't even quite parallel).  I am trying 
to "square up" the image so I can overlay it with some survey data.  Using the 
shearing and rotation transform tools, I can get it close, but I haven't found a good 
way to correct for opposite sides not being parallel.

I tried using the perspective transform to adjust the corners of the image so the 
section lines would be horizontal and vertical.  At first, that appeared to work, but 
it has an unintended side-effect.  When I adjust a corner vertically, it also affects 
the horizontal placement of objects in the image (see 
<http://link-comm.com/temp/perspective.gif> for a screen shot using the transform tool 
- note that everything got "squished" to the left).  I understand that is correct for 
a perspective transform, but it isn't what I need for the map.  

Is there another transform or tool in the Gimp that will allow me to "stretch" the 
corners of an image?  Specifically, I am looking for a tool that will let me move one 
of the corners vertically, adjusting the objects on the map vertically to compensate, 
while leaving their horizontal locations alone.  Thanks for any advice.


P.S.  This may be a similar problem to the one faced by those that are "stitching" 
small image "tiles" together to create larger panoramic images.  I am not familiar 
with how that is done.  Thanks again.
Steve Strobel                           WWW: http://www.link-comm.com
Link Communications, Inc.               Phone: (406) 245-5002 ext 102
MailTo:[EMAIL PROTECTED]              Fax: (406) 245-4889

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