Today’s Question: As a follow-up to the question about media cards, do you recommend always choosing the fastest card available?
Tim’s Quick Answer: In my view there is no need to opt for the fastest media card available unless you actually have a need for that speed. For many photographers a “slow” card will still provide more than adequate performance.
More Detail: The speed rating for a media card indicates the maximum data transfer speed for the card. The speed rating indicated typically refers to the maximum speed at which data can be read from the card under specific conditions. The speed at which data can be written to the card is typically slower than the maximum read speed and can also be significantly impacted by the equipment being used.
If your camera does not support high-speed data transfer, then a faster card won’t necessarily provide you with any benefit. For example, if your camera can only write data at a rate of 30 megabytes per second a card that is capable of write speeds up to 300 megabytes per second won’t provide an advantage.
In addition, not all photographers capture photos (or video) at a rate that requires a high-speed media card. Cameras include a memory buffer where photos are stored temporarily at the time of capture, while waiting to be written to the media card. If you never fill up that buffer with continuous capture of photos, you won’t benefit from a faster media card even if it is supported by your camera.
If you fill up the buffer on your camera you will not be able to capture additional photos until that buffer clears by writing photos to the memory card. If you experience this situation with any regularity, I recommend looking up the specifications for your camera and buying a card that meets or exceeds that speed. If you don’t tend to capture continuous photos regularly, you can opt for a slower (and less expensive) media card.