How far can I run my USB cable from the computer?

USB specification says 15 feet; however, on most cameras I have been able to go 20 feet with a USB extension cord. Some cameras won't work that far away. I have also been able to extend some cameras as much as 35 feet by placing a self-powered USB hub at the 20 foot point from the camera. This doesn't always work so don't be disappointed if it doesn't work for you.
Helpful hint: Plug the hub into the computer first and wait for the computer (Windows) to recognize and configure the hub before plugging in the camera.

A USB hub is an idea, however, most Logitechs do NOT like to be plugged into USB hubs lol. This may work for other brands though.

i have made progress in this i have a 32ft usb lead i have made myself will only work with a usb hum boosting it at the start (from pc) then another usb hub boosting at the end :) hope this helps