The Logitech 4000 webcam is capable of imaging planets and can be modified to take long exposure images to serve as a guide camera. The modification requires a serial port to externally control the camera’s exposure time using a guiding software such as GuideMaster and PHD Guiding.

The long- exposure modification allows the camera to detect faint guide stars, which is a useful feature for a guide camera. The diagram shown here was a modified version of M. Burri’s (2002) parallel port interface for a Logitech 3000 which I have adapted to work with the newer Logitech 4000 and a serial port.
Related link: View all home-brewed DIY astronomy equipment
Night Sky in Focus © Anthony Urbano | Bacoor, Philippines