Making Sense of Memory Cards

Making Sense of Memory Cards

MemoryCards04aSelecting a memory card might seem like a complicated process, but knowing some key pieces of information can help make selecting the right memory card easy. In addition to understanding the different memory card formats and related terminology, photographers and videographers must also consider their use case and workflow to ensure they choose the right technology to meet their needs.



Like flash drives, hard drives, and solid state drives, memory cards have specific capacities which are identified in gigabytes (GB) and labeled on the front of the card. The higher the capacity, the more content (photos or videos) you can store on the card. So if you primarily shoot still images while hiking or camping, you might not need a memory card with a huge capacity. But if you’re planning to shoot a lot of video content, you should opt for a larger capacity card.

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The “x” identifier was originally adopted by Lexar and since implemented by many card brands in the industry. The higher the number before the “x” speed symbol, the higher the performance of the memory card. Each “x” represents .15MB/s. For example, if you multiply our SD 2000x by .15MB/s, you will get 300MB/s.

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A card’s performance is defined as the speed at which your card is able to store and unload images, expressed as “write” and “read” speeds.

– Write speed: Write speed is how fast images are written to a memory card inside the camera.

– Read speed: Read speed is how fast images are transferred off of a memory card to a computer.

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MemoryCards04fSpeed Class:

SD cards have additional symbols to define speed, which can be found on the card label. Designated by the SD Association, a global association that sets industry-leading memory card standards for SD formats, speed class symbols show photographers the required minimum write performance. There are two kinds of speed indications regarding SD cards

– Speed Class  and UHS Speed Class.
– Speed Class: Designates minimum write performance to record video. These range from Class 2 (slowest) to Class 10 (fastest).

– UHS Speed Class: Indicates how quickly video content can be transferred onto the memory card. UHS-I enables maximum transfer speeds of 104MB/s while UHS-II enables maximum transfer speeds of 312MB/s. Within the UHS Speed Class there are two designations, U1 and U3, which represent minimum write speeds of 10MB/s and 30MB/s respectively.

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MemoryCards04gVideo Performance Guarantee (VPG):

VPG comes from the CompactFlash association and is very similar to SD’s speed class. Today, VPG has two ratings which indicate the minimum write speed the card can perform, VPG-20 and VPG-65, with writes speeds of 20MB/s and 65MB/s respectively.

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more at lexar



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