MicroSD cards are becoming increasingly popular, from action cameras to phones, to video game consoles. But you probably should not use one in your dedicated camera, at least not if it does not have a MicroSD card slot.
Why? This is the "pouch", the small plastic adapter that comes with almost all MicroSD cards sold at retailers. This is useful if you need to read the contents of the MicroSD card on a laptop or desktop without a dedicated MicroSD slot, but this card is not designed for constant use. Frankly, it's cheap and it probably slows down the speed of writing your camera.
Let's go back a bit. Modern cameras handle huge amounts of data: images larger than 15 megapixels, as well as HD and 4K video at 60 frames per second or higher. Large format cameras, unlike smartphones, do not have a lot of internal storage – they need to write everything immediately on a flash storage card. The more images and videos you take every second, the more you need your camera to write data.
That's why the "performance" of a memory card is so important: these additional tags, such as "Class 10" and "UHS-3", all deal with the maximum amount of data that the card can handle for reading and writing at a given moment. When you buy a fast and expensive MicroSD card, the card itself can handle that data rate without any problems, but the same can not be said of the SD adapter sleeve provided in the package.
Technically, the sleeve must be able to process the same fast data transfer as the tiny card: the electrical contacts are actually only miniature extensions. And indeed, some of the covers I've tested can have the same score on reading speed tests as the unsupported MicroSD cards that they host. But when they are used with a high-performance camera, the extra steps of the writing process slow down performance.
A practical example: my Sony Alpha A6000 can take six images of 24 megapixels per second. At high shutter speeds, it looks like a small plastic machine gun. But that's a huge amount of data, between 20 and 100 megabytes per second, depending on the content of the image and the quality parameter. When the camera's relatively small hardware buffer is exhausted, a high-speed SD card is needed to take full advantage of the camera's capabilities.
My go-to card is this SanDisk Ultra SDXC. It is designed for a read speed of 80 MB / s – SanDisk does not announce the write speed, but the test on my PC gives me results of about 40 MB / s. Since the shutter speed of the camera is less than the maximum number of shots per second, it takes approximately five to six seconds for the maximum speed to be reached before the camera slows down to slow down. can continue to write, about 55 to 60 images.
I also have a huge Samsung 256GB EVO Plus MicroSD Cardwho normally lives in my phone. It is even faster than the full size SanDisk SD card, with a write speed of about 60 MB / s. So, technically, if I put it in my camera, I should be able to take even more shots at full speed before seeing a slowdown. But as it is a MicroSD card and not SD, it requires the sleeve of the adapter. Despite its superior writing speed thanks to its U3 rating, the camera starts to slow down after only three seconds and about 35 shots. The only variable is the sleeve of the adapter, which can not follow the camera or the card it contains.
There is nothing wrong with using MicroSD cards in devices designed for them. And to be honest, most users who use smaller cards with adapters do not notice the difference or notice it often. However, if you purchased your DSLR or mirrorless camera for fast, reliable performance, you need to purchase a separate, specially designed card – a full-size SD card for most models currently available on the market . They are inexpensive at the moment and the more reliable performance is worth it.