Q: camera connection kit for my iPad lightning To usb not working, device using to much power

How do I copy pictures to my ad from my camera? Apple does not make a CF card reader and after the iso7 update my 3rd party reader does not work at all. I am told I need to use the camera connection kit lightning to usb and carry around the cables.. A bit of a pain but ok. So I get one follow the steps, plug it all in and it just gives me a message device uses to much power! I try a few times same result, I try other cameras still same result I even try a SD card and still the same! What to do now? And don't say spend more money on extra things.