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Two types of speed standards: Speed Class and UHS Speed Class*1, indicate minimum writing performance to ensure smooth recording of video content. The speed class can only work with the combination of cards and host devices that comply with each speed standards.
The table below shows a minimum constant write speed specified for each Speed Class*2.
*1 The UHS Speed Class and Speed Class are not compatible.
*2 The minimum constant write speed of UHS Speed Class and Speed Class are only guaranteed when used with host devices that comply with each speed class.
1MB/s = 8Mbps
*This speed performance is achieved under the conditions specified by the SD Association.
For video shooting, which requires constant real-time recording, you must use an SD card that satisfies the Speed Class requirements by the host device. Otherwise, a stable write speed will not be maintained and may cause dropped frames or, in the worst case, shooting could be interrupted.
UHS Speed Class 3 (U3) is a new standard specified by the SD Association to meet 4K video needs. It guarantees a minimum constant write speed of 30 MB/s (240 Mbps). Panasonic's new SDUD Series supports this UHS Speed Class 3 (U3), which is 3 times faster than conventional Speed Class 10 and UHS-I. This makes it ideal for any type of video shooting from the ultimate 4K, Full HD to standard video.