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If you bought a digital camera in the past decade, the chances are that it stores the images on a SD stands for Secure Digital—memory card. At first glance, this stamp-sized devices do not appear to have changed in the course of the years. But cameras have changed a lot, and SD cards are now faster and can hold more data than that of a few years ago.
“Video is the driving force in the demand for more capacity on the memory cards,” says Brian Pridgeon, director of consumer marketing at Western Digital, the parent company of SanDisk, which makes a lot of different types of memory cards.
Ten years ago, for example, an 8GB memory card would cost about $100. Today, you can buy a 128 gb card with 16 times the capacity for about the same price. Or buy a 32GB card that is four times as large for as little as $10.
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Memory cards are changing in a different way, partly because of the shift of standards, in particular in terms of the video recording. Before you buy a new memory card that you need to consider is how much video you will shoot, and in what form—the HD or memory-intensive 4K.
The first step is to figure out what card the size of your camera or smartphone to accept it, which can usually be found in the manual or on the manufacturer’s website.
There are three SD: SDXC, SDHC and SD. If you are recording a video, you’ll probably need a SDXC card, which is the latest type and has a capacity of up to 2 tb—that’s huge.
SDHC cards have a capacity ranging between 2 GB and 32 gb—bigger is better if you’re shooting video. SD is the oldest format and has a maximum capacity of only 2GB, so it is mainly used for photos.
Some devices, such as smartphones and tablets, with smaller Micro SD cards for storage. These small cards usually come with an adapter that allow them to be used in devices full-sized SD cards. The same specs apply to these cards as their larger brethren.
Although you can buy SD cards in the drugstore or even a supermarket, you are probably a better value and selection if you shop at a camera store or a electronics store. If you are not sure which card you need, you can take your device with you when you shop.
If you’re shopping online, beware of counterfeit. Many consumers are fooled by what seemed like a good deal on a fast 32GB card only to find out that the relabeled 8GB card that just doesn’t work. If you order at Amazon, protect yourself by ensuring that the product is shipped directly from the manufacturer, instead of a potentially sketchy third-party.
The full Capacity
To find out how a pro-shooter makes use of memory cards, I asked Michael Rubenstein, an editorial and advertising photographer based in New York. He suggests that consumers should first focus on ability: “For most people, a 32GB or 64GB memory card should be just fine,” he says. A medium-sized map should be able to capture hundreds, even thousands, of photos, and the scores of video clips.
However, if you shoot with a dslr or mirrorless camera and you want to shoot RAW files, can yield the best quality images, but are larger in size than Jpeg files, you must buy a larger card or several smaller ones, and be ready to swap them if they are full.
If you are recording a video, you can against real-world storage limitations that could affect your shoot. For example, you can record 80 minutes of HD video on a 32GB card but that same card can hold about a quarter of that—about 20 minutes if you shoot 4K (or ultra HD-resolution) video.
The Need for Speed
Because a number of the most advanced cameras, like the Sony a9, it can fire off up to 20 frames per second, the manufacturers have increased the speed of new memory cards. “The higher the megabytes per second (MB/s), the faster the card,” Pridgeon says.
Card speed is composed of two parts: the write speed and read speed. Write speed determines how fast the card can capture and transfer an image or video file from the camera to the card. High speed writing can be useful if you have an advanced camera that can fire off a lot of images at one time.
“A lot of Slr cameras and mirrorless models now can shoot in burst mode, which means that if you take the shutter speed down, it will capture as many images as possible,” Pridgeon says. He explains that all the images are first stored temporarily in the camera’s internal memory, known as a buffer. The camera writes the data of those photos on the memory card. But a camera that is shooting in burst mode the transfer of this data very quickly and efficiently, which is the reason why having a fast card is important. “The card has a high write speed to the buffer to jump,” he says.
Read speed is the second component of the map at speed. “This specification, which is also measured in megabytes per second, refers to how quickly you can reduce the contents of your card to your computer or other device,” Pridgeon says. The fastest memory cards have a maximum write speeds of up to 260 MB/s and a read speed of up to 300 MB/s.
You won’t always see the numbers listed, and sometimes it is difficult to tell them apart. Check the website of the product for both the speed before you make your purchase.
The Correct Specifications for Great Video
If you are recording video, you also need to consider a map of a sustainable speed. But the problem is that there are three different specs that are more or less the same mean. “This is confusing,” Pridgeon says. “But if you’re shooting HD video, you need at least 6 MB/s.” If you shoot with a lower card, your video quality will be compromised, if the records.
Despite the difficult to read specs, here is what consumers need to know to shoot in either HD or 4K video:
- If you’re shooting HD-resolution video, your memory card must have at least a Class 10, U1, or V10—all these have a minimum sustained speed of 10 MB/s.
- If you’re shooting 4K-resolution video, your memory card must be at least U3 or V30. Both have a minimum sustained speed of 30 MB/s.
Make sure that the Card Warranty
If you are looking to buy a new memory card for your older digital camera, check the device’s documentation to see what kind of memory card it accepts. Although newer SD cards are backward compatible, they can be limited by the capabilities of the camera.
That means that you might not be able to access all of the storage capacity of the card. For example, if you have a 128 GB SDXC type memory card in an older camera, you can only use 32GB of storage.
The last, check your card warranty. For a pro shooter like Rubenstein, this is essential. “The most decent memory card manufacturers to guarantee that the cards for a long time. Some for life,” he says. “If they break, send them back, and they send you the new. I do it all the time.”
However, if the cards can break, in most cases, you will not be able to recover the data from them. That is why it is important to back up your pictures often, even if you have a large SD card in your camera.
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