Mac wrote:
Once here on UHH someone told me that I must not love my photos because my camera had only one card slot and I couldn’t back up the photos on another card.
Even now I use the second slot for overflow and not backup.
A second card slot is nice, but I don’t think it’s a must. Like bsprague said a spare card (and battery) in the pocket is no problem.
Before digital, film cameras could only hold one roll at a time—no backup.