Both the US Navy and the Royal Navy painted ships dark gray on the hull and light gray on the superstructure and turrets. USN measure 12 was a graded system with sea blue low on the hull below the first continuous deck, with ocean gray above that. The top of the masts were painted haze gray. This measure was modified with ocean gray above navy blue low on the hull below the first continuous deck (painted parallel to the waterline rather than the main deck). This bold contrast on a horizontal line near the horizon reduced visibility to surface observers and created the illusion of greater range. This camouflage was considered most effective for gunnery engagements with surface units or shore batteries in areas where aerial observation was unlikely. It was used in the Atlantic and European coastal waters from the end of 1942 through the end of World War II. It was worn by shore bombardment ships in the Pacific from late 1944 after the destruction of Japanese naval aviation capability at the Battle of the Philippine Sea. Similar Admiralty standard schemes were applied beginning in 1944 when it was assumed enemy forces would have radar. Ships were painted light gray overall, except for a sea blue patch low on the hull, either between the main gun turrets or the entire length of the hull. In 1935, the United States Navy Naval Research Laboratory began studies and tests on low visibility camouflage for ships. Some measures were deceptive, like a false painted bow wave to give the impression of high speed at all times. Measures making cruisers resemble destroyers were discontinued after causing station-keeping confusion among ships operating in formation. Color schemes included light gray, haze gray, ocean gray, and black. Haze gray was found to provide reasonable protection in the widest range of conditions, and became a standard US Navy paint scheme after World War II. Ocean gray also became a standard paint scheme after the war. Although black is still used for submarines, it was discontinued on destroyers after it had been determined that black ships remained more noticeable than gray ships on even the darkest nights. The US Navy painted some ships sea blue overall for concealment from aircraft. During the Battle of the Coral Sea and the Battle of Midway, ships painted completely blue came under attack less often than ships wearing two-color schemes. On the advice of United States aviators the blue color was darkened and used extensively in the western and southern Pacific from mid-1942 through 1945 to minimize detection and identification by enemy aircraft. Dark blue also proved effective under artificial illumination during night actions. Upper surfaces of aircraft operating from carrier decks were painted a similar shade of blue.