Enable dragging Scroll Bar To Produce A Parallel Movement Of The Image

I am trying to use a VScrollbar and a HScrollbar control on a form to move an image around inside a picture box.This does not involve autoscroll.I am having no problem with the small arrow buttons at the ends of the scrollbars (which generate small increment/decrement ScrollEventTypes) or with clicking on the scrollbars (which generates a largeincrement or largedecrement ScrollEventType).However when I drag the scroll bar back and forth, it does not generate any activity even when I release the scroll bar.How do I enable draging the scroll bar to produce a parallel movement of the image.[code]

related but minor problem is that the scroll event seems to be triggered twice, once when I click on the scroll bar and once after the click event. the first call does not generate any change to the image because the scrollbar value has not yet been changed so it is not a huge problem but seems an unecessary loop to me. Anyway to avoid both handling of the event (pick a different event that is only handled when the scrollbar value is changed?). Why is the scroll event handled twice per mouse click?