Dear all I have a camera Sony dcr 4570 HD plugged with usb to my macbook pro so I'don't know what so the Isight of My macbook pro work but not the acquisition via sony hd cam. Here the patcher I misunderstood why it's not possible to grab any picture via usb. If anyone has an idea about this problem, thank you let me know,
Here my patcher. At right click on toggle to active grab, choose input in radiogroup to send video to videoprojector.