The visual dimension of the view area is fixed for both the cases, that is 300px by 300 px. The view point, in this example (240, 260) is also same in both the cases. However, because we have viewed the normal screen in 1.3 and zoomed it to X4 in case of 1.6, the real coordinate (img.ext) in this case show two different values.
img.x, img.y is a view coordinate of the image.
img.ext is the real coordinate represented by the view coordinate.
Imgxy is the extent of the view/display.