Global Mapper v25.0

Correcting Georeference Imges

ralph058
ralph058 Global Mapper User
edited March 2009 in Technical Support
Hi
When I incorrectly enter data when georeferencing an image, I can tell right away because the image is distortion. I can't see how to fix it without clearing out the image and reloading and re referencing.

Is there a way to correct the georeference points in an image?

Thanks
Ralph

Comments

  • PaulTocknell
    PaulTocknell Forum Administrator Unconfirmed
    edited March 2009
    When you rectify your imagery the first time, be sure to save your control points to a file. That way, if you need to modify the rectification it will be able to load the points. You can then select

    File - Rectify (Georeference) Imagery.

    Load the same file (again) and you'll be able to modify your points.

    Try it out and let me know if it works for you.
  • global_mapper
    global_mapper Administrator
    edited March 2009
    Actually the easiest thing to do is just open the Control Center, right-click on the layer, then select the option to modify the layer position. This will bring the rectification dialog back up for the layer, allowing you to modify the existing control points and add new ones.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • Matt
    Matt Global Mapper User Trusted User
    edited March 2009
    Another thing I've found helpful when I make a really bad mistake with rectification. If you uncheck the layer (making it not visible), then re-rectify, you will see the original, undistorted, image when you use the rectification tool again and you can delete the bad point.

    Matt
  • ralph058
    ralph058 Global Mapper User
    edited March 2009
    Hi
    First, as Murphy would have it, I did it correctly a number of times before I finally decided to deliberately do a bad one.

    Yes, both hints work. I found Mike's latter comment a while ago by accident.