A simple and cheap device called USB hub can expand number of
available USB port. Typical USB hub occupies one computer USB
port and offers four free ports. Make sure the USB hub is USB 2.0
high-speed compatible.
But keep on mind that if more USB devices connected to one hub need
to communicate with a host PC, USB hub shares its single up link line
to the host PC. Although G3 and G4 cameras can operate through a
USB hub, it can negatively affect the camera performance, like
download time etc. It is recommended to connect other USB devices
through USB hub (e.g. the mouse) and to provide the camera a direct
USB connection to the host PC.
4. Alternatively it is possible to use the Gx Camera Ethernet Adapter.
This device can connect up to four Gx cameras of any type (not only
G3, but also G0, G1, G2 and G4) and offers 1 Gbps and 10/100 Mbps
Ethernet interface for direct connection to the host PC. Because the PC
then uses TCP/IP protocol to communicate with the cameras, it is
possible to insert e.g. WiFi bridge or other networking device to the
communication path.
The G3 cameras need an external power supply to operate. It is not possible to
run the camera from the power lines provided by the USB cable, which is
common for webcams or very simple imagers. G3 cameras integrate highly
efficient CCD chip cooling, shutter and possibly filter wheel, so their power
requirements significantly exceed USB line power capabilities. On the other
side separate power source eliminates problems with voltage drop on long USB
cables or with drawing of laptop batteries etc.
Also note the camera must be connected to some optical system (e.g. the
telescope) to capture images. The camera is designed for long exposures,
necessary to acquire the light from faint objects. If you plan to use the camera
with the telescope, make sure the whole telescope/mount setup is capable to
track the target object smoothly during the exposure.
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