Memory Card Speed Ratings

Memory Card Speed Ratings: Class 2 to Class 10..

Memory Cards come in different speed ratings and this needs to be considered especially when using them for HD Video recordings.

Standard Speed Classes:

Class 2 cards are designed for a minimum sustained transfer rate of 2 megabytes per second (MB/s)
Class 10 cards are designed for a minimum sustained transfer rate of 10 megabytes per second (MB/s)

Higher Speeds are also available using the newer UHS Speed Class (designed for UHS devices only)

UHS Speed Class 1 denotes a 10 MB/s minimum write speed
UHS Speed Class 3 denotes a 30 MB/s minimum write speed

Source: https://www.sdcard.org/developers/overview/speed_class/

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