Methods One screw was added to the bottom of axis stayer of the original tripod for the inversion of fixed bulb so that the bulb could vertically project.

• 方法：在原三脚架中轴支撑杆的下端增加1个固定螺杆，用于倒置固定球管，实现球管垂直向下投照，同时加长3个支脚。