1. Format the card in the camera it will be used in.
2. Backup often.
Bob
i was doing a video shoot with my t2i yesterday for a music video. when i was done i wanted to revieuw the shots but when i connected the card to my pc, only the last 4 shots were on the card. what could be the problem? i use a 32GB centon class 10 sdhc card. i also use the magic lantern frimware but the only function i used was the cropmask cinesco2. i also used a battery grip.

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