A filter conversion device includes a first filter, a second filter, a motor, and a microswitch. The motor moves the first or second filter according to a control signal from a processor of the camera. The micorswitch is mounted adjacent to the first filter. A first terminal of the microswitch is grounded. A second terminal of the microswitch is connected to a power supply with a resistor and is connected to the processor of the camera with a connector. When the first filter contacts the microswitch, the microswitch turns on.