Facebook will always resize them, it doesn’t matter what size they start. You might want to start with a large image from the camera and crop to what’s important before uploading. Here the key isn’t the size, but what you want in the picture. Usually the tighter the focus, the more interesting the picture. You can even start this when taking the picture, zoom in really tight every time, then take a step closer, or zoom in one more little bit. Unless you really want to show the surrounding landscape, close cropping or zooming is the way to go, uploading or not. Even if you want to show background, try getting your foreground (person, usually) much closer to you than the background. For example, common mistake in tourist photos, the person to be photographed gets right next to a monument or some other large item, and the photographer has to get way back to get the whole thing. Better to have the person close, and the monument way in the background so you can get it all and still be relatively tight on the person. Sorry, TMI.