Like Donald said, if the object on the beach is too dark, that is because your camera is seeing all the very bright sand around it and choosing an exposure (how much light to let in) for the sand, and not for your object. This is an exposure problem and not a filter problem. You want the camera to let in enough light for the object, not the sand, so go closer to the object and let the camera measure the light coming from it first. That will tell you what exposure to use when you move back away from the object. The sand might then be quite bright on the print, but the object should not be too dark any more.