I can't make everybody happy in this but I think I can answer Sabrina and Hermit's question. Make sure your image viewing prog is set to show actual size, not fit to window. Use the resize/resample function to change the size of the photo to match the maximum size allowed for profile pics. That only applies if you are using your own images.
If you are hotlinking an image from another site then the only way I know of to control that is through HTML.