Because game items are tiny and move rapidly, baseball grounds require more illumination than other sports venues. When it comes to sports lighting, the movement of small and fast-moving items requires more illumination than that of bigger and closer-to-the-ground moving things (such as football). In addition, players' eyes adapt to the dark easily, which would make it harder for them to see well without light. Sports facilities usually have three main categories of lights: outfield, infield, and pitcher's mound. Outfield lights are used in conjunction with outdoor screens to help managers monitor games and make adjustments during timeouts. These lights are typically high intensity discharge lamps powered by 12 volts direct current from a generator set off of one of the stadium's power lines. The lamps usually range in height from 4 feet to 6 feet, depending on the size of the screen, but can be as tall as 30 feet if needed. They produce a wide beam of light that covers a large area, which is necessary because there are so many people watching the game through the cameras. Managers use signals from handheld controllers to turn these lamps on and off. Infield lights are used at each base station on the field to provide directionality by shining into specific areas for first basemen to find. These lights are typically low-voltage halogen lamps powered by 12-volt batteries connected directly to the baseboard inside the station.