27" iMac i7

I'm a commercial photographer who shoots with a Canon 5D II camera that is usually shot "teathered" to my Macs via a 14' USB cable. That is until I bought a new i7 Core 27" iMac. With the long cable, the computer cannot see the camera, though the camera does see the computer. If I use a 6' USB cable there is no problem with communication at all, but a 6' cable is too restrictive to be useful in the studio. Anybody have a suggestion? Apple claims to have never heard of the issue, however when I went to an Apple store and connected the camera to their 27" i7, it still did not work. It ain't me, it's them.

I believe what you need is a USB extension repeater cord because I think you are near the maximum range of USB technology. I've been told USB doesn't work past a certain length so if you want a longer cord you need a repeater.

I've experienced this problem a few times myself with other electronics and getting a repeater extension cord works. Basically use your shorter 6' USB cord and then get a long repeater cord.