What you need:
You will need two identical external drives and a copy of Carbon Copy Cloner. CCC is free. The drives could be USB 2 if all you are doing is backing up. If you plan on editing with the drive(s), you'll want firewire. Each needs to be large enough to contain the raw card contents for the duration of your gig.
The Process:
At the end of the first day's recording, connect the two drives to your computer (if firewire, daisy chain them / if USB, you'll need two USB 2.0 ports)
On the first hard drive (Drive 1) create a folder - call it BigDealLecture
Inside of BigDealLecture, create a folder and use the nameing convention "BDL_Date_card number for that day" - so if you used 2 cards today, you should create BDL_2012-02-15_01 and BDL_2012-02-15_02
Attach your card reader or camera to the system.
Lock the cards so they can not be erased
Insert Card 1 into the reader
Select ALL contents of the card and copy them to the folder you created for the first card for today
When it is complete, eject the card, insert card 2, copy its contents to the folder for card 2
eject the card
Launch CCC and do a clone of Drive 1 to Drive 2. You can set it to do a complete block by block clone or an incremental backup. Either will work.
When finished cloning, test a random sample of the clips on both drives to make sure they work.
When satisfied the copies work, put Drive 2 in the hotel safe.
Put the Drive 1 in a place where you can grab it if there is an emergency in the night and erase the cards to get ready for the next day.
Take Drive 1 with you to the lecture site the next day.
Rinse and repeat daily.
When the conference is over, send one of the drives via FedEx or some other same day service to your office. Pack the second drive in your bags for the trip home.
A note: If you have enough downtime durning the conference between obligations, you can do the transfer from the cards to Drive 1 on site and do the clone when you get back to your room. Don't unlock and erase the cards until you are satisfied the copy/clone process was without incident.
Have fun.
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