BobART
tab,
under 
Images,
right-click 
Image name,
and click Change Origin.When you load an image from the BobART tab, the image displays in the graphics area with the reference point (origin) located at X0Y0Z0. The origin for the image is the bottom-left corner of the image. If you need to relocate the image in the graphics area, you use the Image Origin dialog box.
To access the Image Origin dialog box after an image is loaded:
BobART
tab,
under Images,
right-click Image name,
and click Change Origin.View the Image Origin dialog box
Origin
Type values in the X-, Y-, and Z-boxes to define a point for the new location of the image origin. The image is moved using the origin (the bottom-left corner) of the image. Click OK, the image is moved to the new location.
