This post was updated on October 18, 2017.
Memory cards are one of those areas where photographers often try to save some money. While it may seem appealing to only spend $25 on a memory card instead of $80, how will you feel when you capture one of your best ever photos, only to find out that the memory card got corrupted and you've lost your data?
However, you can also spend too much on a memory card. Spending $200 on a memory card is almost always a waste of money, because the newest specs for card speeds generally are not accessible by cameras for a few years. Camera speeds need to catch up to be able to address the fastest cards. Similarly, the highest size cards (such as 256gb cards or 512gb cards) simply cost too much and few photographers will fill that large of a card.
The card I recommend and have in my camera most of the time is a Sandisk Extreme Pro 128gb card (available on Amazon.com). I'm not aware of any cameras from major manufacturers whose cameras can address more speed than this card can provide. It will keep you shooting fast, and I have always found Sandisk cards to be very reliable.
A 128-gigabyte card will hold 4,266 large raw files (30 megabytes), so I doubt you'll fill the card in a full day of shooting unless you're shooting timelapse. I find that the highest risk of losing data is when you use two different memory cards in a single day. The chance of accidentally misplacing a full card in your bag, or overwriting the wrong card is too high. I like to have one single card that is big enough to handle everything I can shoot in one day, and then I offload that card all at once to a computer before switching cards.
I used to recommend Lexar cards, but they have gotten out of the consumer memory card business and are just focusing on SSDs.
There are 4 basic things you need to look for when purchasing your next memory card for your camera. When it comes to photography, you do not want to be buying just any memory card or the cheapest card memory card because you will most certainly be getting what you pay for.
TYPE: DSLRs can accept either a Compact Flash (CF) or a Secure Digital (SD) cards to store your images. Higher end DSLRs will accept both types of cards to save the photos on. Anymore today, you will more commonly find just SD cards are accepted into the camera. If you know your camera is older – but sure to read in your manual what type of SD card it supports. You have SDSC (SD Standard Capacity), SDHC (SD High Capacity), and SDXC (SD Extended Capacity). Most of the memory cards you find today will be the SDXC type and your camera must be compatible with this version of the technology in order to even recognize the card in the camera. You can tell what type of SD card it is by simply looking on the label – it is your camera that you want to look into more closely.
SIZE: There can be a lot of debate on what is best for you when selecting the capacity of your next memory card. Evaluate your workflow and select a size that makes sense to you and your photography. Here at Improve Photography, we buy some of the bigger memory cards just so that we don't lose them and get them mixed up. We have a primary card we use in the camera with a backup memory card in every camera bag we have in case we forget the card in the computer or run out of memory on a long shoot. Consider looking at a 32GB card or greater when looking for your next memory card.
SPEED: Memory cards have been rated based on a class system. A system that guaranteed a minimum file transfer speed between the device and the card itself. The highest class on a memory card is a Class 10, which means you have a guaranteed 10MB/sec. file transfer speed. But makers of the card will often advertise the maximum card speed should all conditions be ideal. However, the CLASS 10 we have all looked for has now been surpassed by the new UHS-1 (Ultra High Speed – 1) and are seeing data transfer speeds of up to 104MB/sec. These UHS-1 cards work best in native host devices, so look in your manual for your camera to see if it supports UHS-1… and if your camera was made in the last 1.5 years, then you should be good to go for this.
BRAND: We highly recommend that you purchase a SanDisk or Lexar card from a reputable retailer. These two companies perform extensive testing to ensure that their product will work in as many products as possible without any error or corruption. The more affordable brands (such as Transcend) will skip the testing to save money on the overall cost of their product. They will work fine and you will find the same speed on them but whether or not they will last you for a while is something to be debated. Note: Be sure to buy your SanDisk or Lexar cards from a reputable retailer that you know or have heard of. Because these are popular brands, it is easy for someone to sell you a knock-off version of the card by simply slapping on a sticker and calling it a SanDisk or Lexar memory card. So beware, even if you are buying on Amazon.