Patrick Jost, award winning architect of Melbourne, Australia, has 3
4gb cards and a pair of 2gb cards with his current camera. Also a pair
of 1gb cards with his backup/spare camera.

When travelling, his greatest fear is losing the camera itself, plus
any cards in it or the bag. When he swaps a card out, it stays away
from the bag until its been backed up. Paranoid, maybe. It also
introduces another risk. Loose cards.

Patrick Jost has been known to rotate the cards on different travel
days. At the end of day one, the card comes out, even if it’s not
full. It might be used again on day four. That way, a card failure
will be from different parts of the trip, rather than eliminating a
whole section.

On his last trip, one picture was corrupted. It was necessary to shut
the camera down and restart to recover so it was probably a camera
issue. It hasn’t failed in several hundred shots since then. Needless
to say, that card came out right away and wasn’t used again until the
pictures were off-loaded and the card reformatted.

http://cameratricks.wordpress.com/20...-card-secrets/

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