Take a look at your memory cards – chances are you have either an SD (Secure Digital) or microSD card, maybe both. SD (and microSD) has become today’s standard memory card format as it is widely accepted in both consumer and professional-grade cameras, but did you know that not every memory card is the same? For SD and microSD cards there are two different types: UHS-I & UHS-II. From the front you may not notice, but when you take a look at the back the difference is evident. Here, we’ve quickly broken down the differences between UHS-I and UHS-II SD cards, seen and unseen.

UHS-I vs UHS-II:

The UHS-I bus interface allows for transfer speeds up to 104 MB/s, while UHS-II boasts significantly higher speeds up to 312 MB/s. This is due to UHS-II cards being designed with two rows of pins, rather than one like UHS-I, which allow for two lanes of data transfer. The higher the transfer speed, the less wait time and sooner post-production can begin. This is ideal for photographers and videographers who need to quickly unload large amounts of data and get back to shooting.

VIDEO SPEED CLASS:

Video Speed Class (V10 to V90) indicates an SD card’s minimum sustained write speed (e.g. 10MB/s for V10 | 30MB/s for V30 | 60MB/s for V60| 90MB/s for V90). UHS-I SD cards are only capable of V10 & V30 speeds, while UHS-II SD cards can perform at V60 and V90 speeds.

V10:  SD cards rated V10 are ideal for still photography and Full HD 1080p video recording @ 30fps.

V30:  SD cards rated V30 can handle flawless 4K video recording @ 30fps and RAW burst photography.

V60 & V90:  SD cards rated V60 and above are optimized for 6K & 8K video recording at high frame rates & bitrates, as well as simultaneous multi-file recording (e.g. RAW + JPEG, multiple video streams created by 360º cameras, video + still + GPS data, time-lapses, etc.)

What happens if I use a UHS-I card in a UHS-II host?

Your UHS-I SD card will work, but will be limited to the maximum speeds that the card is capable of achieving. It will not be able to utilize the optimum speed allowed by the host.

What happens if I use a UHS-II card in a UHS-I host?

Your UHS-II SD card will work, but will be limited to the maximum speeds that the host is capable of allowing. It will not be able to utilize its fullest potential.