Are you confused about all the different SD card abbreviations or just want to refresh your knowledge? In this article, we’ll clarify the big questions: SDHC vs. SDXC – which is best? We’ll also provide quick tips to ensure a long lifespan and reliable operation for your SD cards. Lastly, we’ll touch on the topic of data loss and data recovery.
What is the Difference Between SDHC vs. SDXC
The key differences between the two memory card types are compatibility and storage capacity. Namely, SDHC cards are compatible with SDHC and SDXC devices and have a storage capacity of up to 32 GB.
On the other hand, SDXC offers a maximum capacity of 2TB, which is no less than 2000 gigabytes. However, SDXC doesn’t work with SDHC devices. Both can also have the same available speed class ratings.
SDHC Cards Demystified
SDHC is short for Secure Digital High Capacity, and the standard was introduced in 2006. As of writing, SDHC is the most common card type for digital cameras, including DSLR, mirrorless, and camcorders. This is due to their maximum capacity of up to 32GB, sufficient for most photographic work. However, size is not the only factor when choosing the right SD card. Transfer speed is also worth considering.
SDXC – A Quick and Easy Explanation
SDXC was initially announced in 2009 and stands for Secure Digital eXtended Capacity. The SDXC standard offers up to 2TB of storage. Since SDHC was introduced, this is a 60x capacity increase over 3 years. While 2TB of storage might sound like any videographer’s wet dream, keep in mind that speed is also a critical factor to consider.
Both SDHC and SDXC come in the same, familiar form factors. Both also tend to have several other acronyms written all over them. A popular one is the UHS speed class, which segues us right into the next topic.
UHS-I vs UHS-II vs UHS-III
Whenever you look at any newer SDHC or SDXC card, there is often a U symbol with a number. The U refers to UHS – yet another abbreviated standard, which stands for Ultra High Speed. While UHS-I provides write speeds of up to 104MB/s, UHS-2 handles up to 312MB/s. The UHS abbreviation is, in fact, the name of the speed bus used in the particular product.
UHS-3 will write with speeds up to 624MB/s. This is why it’s crucial to understand your needs in terms of write speed. If you plan on shooting 4K video, look for a card that can write at 300 megabytes per second. If you expect to be doing frequent burst captures, say, in sports action or wildlife photography, blazing-fast write speeds are your friend, too.
Moreover, you might notice a physical difference between your memory cards. Standard SD and UHS-1 cards have a single pin row, while UHS2 and 3 cards have extra rows. This means more contact surface with the host device = faster write and data transfer speed.
There is also the video speed class, which is abbreviated to V speed. It supports a sustained minimum write speed of 90MB/s. Compared to UHS class SDHC and SDXC cards, the standard SD (Secure Digital card) memory card standard supports maximum speeds of 25MB/s.
Furthermore, the above-mentioned data transfer speed and capacity differences are similar across the different card formats – whether you have a standard, mini, or microsdxc card. In essence, to get optimal write speeds, your camera, and your card should be fully compatible – that’s why it pays to do some research before spending potentially hundreds of dollars on multiple SanDisk Extreme PRO cards.
How is the SDHC Card Format Different from SD?
In short, maximum storage capacity. While standard SD tops out at 2GB, an SDHC card can store up to 32 gigs of data. The write speed varies according to the speed class of the respective card. The actual file system is different, too. The regular SD cards feature Fat16, while every SDHC card has Fat32.
The physical shape of SDHC cards is exactly the same as the good old SD cards. The transfer speed depends on the speed class of the card and whether there is UHS.
SDXC and SDHC Memory Card Usage Tips
Memory cards are sensitive, as they are based on flash memory. That’s why some common sense goes a long way when handling them. Your memory cards should never be exposed to heat, moisture, physical stress, or magnetism. Yes, this includes magnetic locks on bags.
When not in use, it’s best to keep your storage media in a designated protective storage case. You should also keep them clean from dust, grime, and anything else that’s not supposed to be there. Ensuring that the connector pins are clean will provide a perfect connection to the host device. But have you ever wondered how to prolong the lifespan of your memory card? If so, keep reading.
Making Your SDXC or SDHC Card Last Longer
No matter if you’re a seasoned pro or just getting started, the lifespan of flash storage memory cards is a critical concept to be mindful of. The better you take care of your memory cards, the longer they will work with zero errors and data corruption.
That’s why, for example, professional wedding photographers tend to use brand new, genuine brand-name cards for every gig. Then, after importing the photos, the cards are stored in a fireproof safe. Some of the most highly appraised SD cards amongst professional users are from Lexar and SanDisk. That’s due to near-zero failure rates reported in the community. That said, Panasonic, SanDisk, and Toshiba are all the SD Association founding members and offer highly reliable quality products. Just make sure that you purchase genuine brand-name SDHC cards.
You should optimally bulk-delete the files using the computer, tablet, or phone instead of the camera. If you have a built-in card slot – great. If not, you can use a card reader. This way, you can minimize the total amount of erase cycles performed – which prolongs the card’s life.
How to Tackle the Risk of Data Corruption on Your SD Card
All SD cards have a wear controller that balances the demand across the card’s different memory segments. This enables most cards to deliver approximately 100.000 erase cycles before the data integrity gets compromised. This means that even with daily card formatting, it’s theoretically not unreasonable to expect up to 50 years of service from an SD memory card. If a card is not in active use, except the one photoshoot, it might even survive up to 100 years in dry, dark storage.
However, even the most reliable technologies are bound to fail once in a while. Even if the chance is way under 0.1%, losing irreplaceable, valuable work is never fun. Luckily, we have the concept of redundancy to mitigate the risk of card failure.
Here are some quick tips to help you avoid data loss altogether.
- Never eject the card while the camera is on.
- Don’t take out the battery while your digital camera is writing to the card. Most devices will finish writing before powering off, but this only works with the battery installed.
- Use a camera with dual card slots – and set it up to write to both cards simultaneously. This way, even if one card fails, there is an automatic backup.
- Bring an extra camera and possibly even a second shooter. Then, even if a card or the camera itself has a critical failure, you’re still able to keep shooting – and deliver your service.
Data Recovery Software for SD Cards
Sometimes, mistakes happen. Perhaps you delete the right photo, or worse, hit format by accident. In this case, there are excellent data recovery tools for both Windows and Mac users. I have personally used DiskDrill with great success, but here is a shortlist of some of the most popular photo recovery solutions in no particular order.
Some apps are designed specifically with photos in mind, while others work with general data and even smartphones. For even more great alternatives suggestions, go to https://alternativeto.net/.
While the user reviews can be super helpful, make sure they are up to date. Often it pays off to try a few different programs to decide which one works best for you. Don’t wait until you need it – because when you do, you’ll be glad you prepared.
Which Memory Card Type to Choose
First of all, no matter what you do, get a genuine product. While it’s possible to find Chinese knock-offs for a fraction of the price, there are no guarantees for data integrity with such products.
The world of SD cards can be technical, complex, and seem overwhelming. To make things simple, you’re most likely OK if you get an SDHC card by a renowned manufacturer like SanDisk, Panasonic, or Lexar. Aspects like capacity, write speed, and price, come down to the unique use-case and your budget.
Conclusion re SDHC vs SDXC
While SDXC cards offer larger storage capacity, the SDHC vs SDXC question comes down to your needs. As long as your host device supports the newer SDXC standard, there is no harm in getting extra storage space. On the contrary, if you’re rocking an older unit that only supports a standard SD card or SDHC, you won’t be able to use SDXC – unless you upgrade your digital camera.