When saving a worksheet as an image, the worksheet is rendered as if for printing, in other words if the minimal rectangle containing the populated cells, along with margins, headers and footers, does not completely fill an A4 page (default) then the rest of the A4 image is all white space.
My application is to insert an image of the worksheet into the body of a Word document, with text flowing as close as possible to the "minimal rectangle" of the worksheet. This does not work very nicely if the image is produced as an A4 page with lots of white space.
E.g. something like ImageSaveOptions.OnlyArea = true.