Memory Card Capacity: Which Size Should You Select?

An In-Depth Guide to Selecting the Perfect Memory Card for Your Needs

As the need for portable and accessible data storage grows, memory cards have evolved significantly. From SD cards to the most recent SDUC cards, the range available might seem daunting. Recognizing the importance of choosing the appropriate memory card based on size, class, brand, and capacity is pivotal for effective and wise data storage.

Do you consider yourself informed enough? If you do, that's fantastic. If not, there's no cause for concern. This article is designed to cover all the information you require about the varieties of memory cards, classes, sizes, speeds, etc.

Selecting the Appropriate Memory Card Capacity

Prior to purchasing a memory card, it's essential to be aware of the storage or memory capacity options available in the market. Various sectors, from photography to the music industry, not to mention the broader digital and electronics markets, all utilize memory cards for their compact data storage solutions. Each digital domain demands its own storage capacity, which has been cleverly fulfilled by the evolution of memory cards. 

 Now let's explore the different types of memory cards based on their capacity:

Basic SD Card

 You may be familiar with the SD card, also known as a Secure Digital card, which was the preliminary form of memory card. However, it's no longer so common due to its limited size. These standard SD cards support storage up to 2GB. They are frequently recognized as SDSC or Secure Digital Standard Capacity.

SDHC card

<-p> Should you require a storage capacity exceeding 2 GB, then an SDHC card is your ideal choice. SDHC cards offer more storage than the classic SD card. As the next step after SD, SDHC or Secure Digital High Capacity offers increased storage compared to its predecessor. SDHC cards provide a maximum storage range up to 32 GB.

SDXC card

 SDXC cards introduce an even greater capacity. As a third-generation memory card, the Secure Digital Extended Capacity is designed to offer expansive storage options. SDXC cards can handle a storage capacity of up to 2 TB, equivalent to 2048 GB. 

SDUC card

 Presenting a solution with massive storage capabilities, the SDUC, or Secure Digital Ultra Capacity, is the latest innovation in memory cards as of 2018. SDUC cards offer unparalleled storage up to an impressive 128 TB.

 Given that SDSC cards are limited to smaller storage uses, they have become less popular compared to SDHC and SDXC, which present superior capacity options. We are grateful for SDHC and SDXC cards as they support the increasing demands of complex applications, elaborate games, and the capturing of high-resolution images and videos. 

 A wide array of devices including smartphones, cameras, laptops, and drones accommodate all types of memory cards tailored to individual needs. When opting for memory card capacity, select options that align with your specific requirements and budget. For those in need of extensive and superior storage, SDUC cards are available and could become a common choice in the coming years.

Physical Dimensions of Memory Cards

 One critical element you should certainly consider is the physical size of the memory card!

Memory cards are categorized into three major types based on their physical size: Full-size SD cards, Mini SD cards, and MicroSD cards.

Currently, the two predominantly used Secure Digital card sizes are the micro SD card and the full-size memory card.

MicroSD card

These cards are significantly smaller than the standard Secure Digital card. In Asia, MicroSD cards are called Trans Flash, or TF cards, and measure 15mm x 11mm. They frequently feature in portable digital devices like mobile phones.

MicroSDHC

The introduction of the MicroSDHC, an evolution of the SDHC, provided a data capacity of up to 32 GB along with a transfer rate of 10 MB/sec. These cards are specially made for gadgets that require compact-sized MicroSD cards.

MicroSDXC

MicroSDXC cards mirror the storage capabilities of their SDXC counterparts. Similarly offering a storage minimum of 32 GB and a maximum of up to 2 TB, these cards fit perfectly into devices with micro slot compatibility, thus extending storage options. 

MiniSD cards

MiniSD cards are slightly larger than MicroSD cards, measuring 21.5 mm x 20 mm. Sandisk Corporation introduced MiniSD cards in March 2003, and they are commonly used in mobiles and cameras.

MiniSD cards cater to compact, newer hand-held devices such as GPS systems, digital audio players, portable media players, and digital cameras, providing the same functionalities as standard SD cards.

Full-size memory cards

Full-size, or standard SD cards, are intended for larger digital tools. These cards are widely used in DSLR cameras and sizable video cameras and are the most substantial of all types, with a 32mm x 24 mm size dimension. 

Considerations Regarding Memory Card Speed

 Should speed be your paramount concern, then it's important to analyze the factors for selecting a suitable memory card to meet your storage needs effectively.  Memory cards can be grouped into two categories based on speed: Memory card bus speed and Memory card speed class. These are distinct from one another.

Memory Card Bus Speed

The bus speed of a memory card refers to its transfer speed. Secure Digital cards offer a variety of bus speeds or transfer rates. The appropriate bus speed will vary depending on the file format or media to be captured. The bus speed of SD cards also varies from brand to brand and from device to device, thus influencing data retrieval speed.

 Memory cards are classified according to bus speed as follows:

• UHS-I or Ultra High Speed-I with a transfer rate up to 104 MB/s. However, the maximum bus speed typically is around 95 MB/s. As bus speeds vary between devices and card manufacturers, the real-world bus speed may range from 50MB/s to 95MB/s.

•  UHS-II or Ultra High Speed-II with enhancements in bus speed, offering transfers up to 312 MB/s. The actual speed achieved is typically close to 299 or 300 MB/s.

•  UHS-III or Ultra High Speed-III introduces an exceptional transfer rate of 624 MB/s in Secure Digital cards.

•  SD Express incorporates the evolving landscape of technology, debuting in 2018 with astonishing 985 MB/s transfer rates.

Memory Card Speed class

This specification plays a vital role in videography as it concerns the sustained minimum write speed. For continuous and clear video capture, maintaining a consistent minimum write speed is necessary to prevent frame skipping.

 The following are the distinct speed classes available for memory cards:

Speed Class

Speed class is indicated by a 'C' symbol followed by a number, such as C2, C4, C6, or C10, indicating the minimal sustained write speed in MB/s.

UHS Speed Class

 The UHS Speed Class measures sequential write speed, depicting it with U1 or U3 (1 or 3 inside a 'U'). U1 indicates a 10MB/s sequential write speed, while U3 offers 30MB/s.

It's important to differentiate UHS-I and UHS-III from the UHS speed classes 1 and 3, respectively.

Video Speed Class

Specifically tailored for high-resolution video recording, the Video Speed Class is marked with a 'V' followed by numbers 6, 10, 30, 60, or 90. It's suitable for 4K and 8K videos, offering 6-90 MB/s sequential write speeds.

Matching Memory Card Capacity with Photography Needs

Action Photography

When shooting action or sports photography, you'll likely need fast cards capable of managing 41 MP images in RAW format at burst rates of 8fps. Utilizing a UHS-II card with a U3 class is advisable to prevent bottlenecks in your camera's memory buffer.

Landscape Photography

For landscape photography endeavors, opting for an SD card with Ultra High Speed-I bus and a minimum of speed class 6 is suitable for capturing images. However, considering an upgrade for future proofing is also a practical choice.

Accommodating Memory Card Capacity in Videography

• For 1080p videography, U1 speed class cards are sufficient, performing well at 30 frames per second. A card with speed class 10 is also compatible with this resolution.

  
  

• If you aim to capture 1080p HD videos at 10 MB/s or undertake full-size raw video shoots, then U1 cards with a class 10 designation are suitable. Cameras with more powerful sensors may require even faster cards to manage the data flow.

Additionally, the SD bus type of your camera, whether High-Speed or UHS, will affect speed. Modern cameras tend to support UHS SD bus slots, making device compatibility an important consideration when selecting a memory card. 

• For 4K video recording, at minimum, a U3 class is recommended. Although class 2 is the slowest in comparison, contemplating the speed class rating of your device used for 4K shoots is crucial.

To achieve higher quality, consider newer VSC-rated cards, such as V10, which are ultra-fast and accommodate simultaneous file recording. For premium-quality 8K video captures, V90 cards provide the most outstanding and superior performance.

In summary, choosing the ideal memory card entails a comprehensive understanding of various aspects, including capacity, size, speed, and intended application. Whether you’re seeking SD, SDHC, SDXC, or SDUC cards for storage or cards offering high sequential write speeds for videography, being knowledgeable about these factors guarantees the selection of the most suitable memory card for your needs.

For detailed information on top-tier memory cards and their compatibility with cutting-edge photographic and videographic tools, please visit Enlaps.