There are several ways to get the P-ID number of a Canon Powershot camera: * From the firmware information page (Ver.req - method) * From the USB driver log on a Linux system, with lsusb - it's the 2nd part of the USB device ID, e.g. 04a9:318d for the SX10 * From the Windows USB driver information page in the device manager (only available when the camera is connected, must be in PTP mode) * From the Windows registry: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\USB, search for "Canon" / your camera model there... sample: HardwareID = USB\Vid_04a9&Pid_318d&Rev_0002 USB\Vid_04a9&Pid_318d for the SX10