Timage does not have a canvas it self, the canvas property on timage is a courtesy and it internaly links to a bitmap object which has specific size and if drawn once on it the bitmaps dimensions freeze and they are no longer changed as the image is resized this ofcourse means that the bitmap will be stretched in order to fit in the image's visible area. It would be for the best to clear the old bitmap every time the Timage is resized by assigning null to Image's picture property.