Q: CF cards and iPad

Are you sure you mean cf as IN compact flash

http://thefuntimesguide.com/images/blogs/lexar-compact-flash-card.jpg

And general thing that copyring from external use the power it use period

Of cause if it's USB then using an ext Powered USB hub would Solve power issues

If you have a CF-only card reader then that would probably have a better chance of working than a multi-card reader - I have an old Belkin CF card reader that still works. Or does your camera support PTP (picture transfer protocol, Pictbridge) and/or mass storage device for direct transfer to the iPad ?

BigCat,

I've gone thorough this issue myself.  I shoot a Canon 7D and was interested in backing up my photos directly on the iPad.  After thinking it through, I concluded it is really not a practical solution for several reasons.

First, there is no suitable CF card reader that plugs directly into the iPad.  MIC makes one, but reports are spotty about how reliable it is.

http://store.micgadget.com/card-readers/280-ipad-2-cf-card-camera-connection-kit .html

Second, the iPad memory simply isnt big enough to hold a lot of photos, especially if you shoot RAW like I do.

In the end, I gave up on using the iPad as a storage device while traveling and instead got a MacBook Air with a 500GB G-Tech Slim Drive.  This is a much better solution.

A camera that supports PTP and/or mass storage device can be connected directly to the iPad for copying photos and videos - the kit has two parts, an SD reader and a USB connector for connecting to your camera (it can also be used to copy photos from iPhones and iPod Touches). I've used it to copy directly from Canon DSLRs.

Using the CCK : http://support.apple.com/kb/HT4101

Both of my primary cameras use CF cards. I transfer photos from those cards by putting the card in a camera and connecting the camera to my iPad with the Camera Connnection Kit. It's a little cumbersome moving cards into and out of the camera but I've never had a transfer fail.