Min, Max, Sustained Speeds Explained

You’ve bought a new camera, identified the type of memory card you require and even did research on which capacity might be the best fit. Now, the sales associate asks if you primarily shoot stills or video and which speed of card you need…you stumble, bite your bottom lip and throw your hands up in the air (because at this point you simply just don’t care). “Speed? What speed of card do I need?” You have no idea. Let’s do a quick break down on memory card speeds so that you can make an informed decision.
These are the minimum speeds that the card will function at, either transferring data from the memory card to a computer or writing data to the memory card from the buffer. For SD memory cards, these are indicated by a Video Speed Class rating (V10 / V30 / V60 / V90), meaning a minimum speed of 10MB/s for V10 or 90MB/s for V90. This is known as the valley of speeds. Applies to both read and write speed.
These are the maximum speeds that the card is capable of reaching in the most optimum settings while either transferring to a computer or writing to a memory card. Many times noted as MAX Transfer Rate, as this is typically used in most marketing to show the best possible speeds available to that memory card. This is the very peak of speeds. Applies to both read and write speed.
These speeds have grown to become the golden ticket for true photographers. Not for grandma who snaps one photo at a time, but rather for grandpa who wants to photograph eagles soaring over the mountains in continuous RAW. Sustained speeds are exactly what you’d expect, the true sustained speeds your card is capable of maintaining. There are no peaks or valleys, only one fairly flat line of capability. Sustained speeds are incredibly important when shooting more demanding types of photography or videography in the latest cameras.

Simply put, speed matters. It matters while reading or downloading data from your card to your computer, especially if you’re a working professional and your workflow involves editing those images or video before giving them to your client. It matters while you’re shooting action sports, 8K video and other heavily demanding data modes. The latest cameras require memory cards with professional-level speeds, users are demanding cards with those speeds, and Delkin delivers those speeds.

Email us today so we can make some recommendations on the best speed of card for you, your camera and your shooting style: jsherry@delkin.com