Like Tomas said, you can't write to card at the same time with Nikon so (thanks to a suggestion from JasonRS in another thread) I set up an Automator Instruction (on Mac) to backup images in real time to a second HD for security.
Hiya mate,
Isn't this back up still dependant on the transfer from camera, via USB to laptop? I.E if you experience a crash or the connection is broken, there will still be a loss of files?

Yes, that's true... it's a solution to a different problem I guess!
If you have a crash or the connection is broken though, won't the camera start writing to the internal card while the connection is down... so you still have the images saved in camera?![]()
The worst instances involve experiencing a crash or connection breakage during a file transfer. Thus, your files in mid transfer = vanish into the ether, forever lost.![]()
This Nikon Camera Control suggested by a TP on a recent Flash Course does save to CF as well but not sure if it covers Macs.
http://www.diyphotobits.com/download-diyphotobitscom-camera-control/
Dave
No doubt someone will probably say I'm wrong, but isn't the maximum length of USB cable 5m, although this can be increased with active usb cable extenders.
I've used the software from diyphotobits on my D5000 and can confirm it does transfer to the computer and save to memory card at the same time![]()
Found this link useful for setting up Lightroom: http://www.scottkelby.com/blog/2008/archives/1207