Blackmagic's recommended cards, from Sandisk and Delkin, are both expensive. As of this post, the Sandisk 64GB Extreme Pro is $132.37 and the Delkin 64GB Elite is $131.51.
64GB would be a lot of memory for any other camera. But it only gives you 37 minutes of recording time with the BMPC.
Fortunately, there is another option, which will give you over an hour of recording time. Adata UHS-I cards record at the same advertised 45MBps write speed as the Delkin, and you can get a 128GB Adata Premier Pro SDXC card for $125.
I went out and shot with the 64GB version of this card today, and had no issues. The camera recognized the card and there were no dropped frames.
Twice the storage for less money, not a bad deal.
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