Dave (Thome),
An untested idea, take Dave (Frankenbach's) idea and place your image control in its own form. Enable the form's scrollbars. If you resize your image controll and its bigger than its parent form, then the parent form should automatically enable its scrollbars.
If you're using a version of VFP prior to 9.0, the max size of a scrollable form is 2x the size of your display. VFP 9 removes this restriction so your forms can be arbitrarly big (I'm sure there's a reasonable limit, I just don't know what it is).
Does this help?
Malcolm