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Old Jun 22, 2011, 12:14 AM
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Originally Posted by xamindar View Post
Are you sure that is the card write speed? I was reading the thread back then and I always took it to mean those numbers were the bit rate of the video which is something entirely different than card write speed. If those posts really were talking about card write speed then you are right. But if it was video bit rate, that would all depend on how the video encoder decided to encode the video before writing it to the card (a decision that seemed to depend on how the card was formatted, not the card's write speed).
Bad use of terms on my part... write speed TO the card (i.e. total average data rate output by the camera and written to the card), not write speed OF the card (e.g. as measured by CrystalDiskmark, etc.). Write speed of the card is obviously faster than the data rate being written to it since no dropped frames. But the formatting of the card affected the data rate the camera put out, which was the interesting part. And since the SD cards have the ability to store key data about it's characteristics that can be read by the host device, this was the only credible explanation for why that would occur.
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