Every dSLR camera requires a memory card if digital data is to be stored; however, consumers find that memory cards are rarely included when they purchase the camera. For dSLR cameras, memory cards are a necessity. The good news is that most of these cards are affordable.
Though memory cards don't impact image quality, different cameras and users have varying requirements. Additionally, there are numerous types of memory cards that fit dSLR cameras. This guide covers important facts photographers need to know.
Types of dSLR Camera Memory Cards
Users can choose a Compact Flash (CF) or Secure Digital (SD) memory card, though there are other types that are specifically designed for certain uses or cameras. The kind of camera one has and how one uses that camera are the deciding factors in what type of memory card to get. Prior to buying, ensure compatibility.
Compact Flash (CF) Memory Cards
The thick and durable CF cards arrived in 1994 and are commonly seen in more advanced cameras, as they store data quickly and have high storage capacities. Cameras like the Nikon D300, Olympus E-3 and Canon EOS 400D use these kinds of memory cards. Ultra Direct Memory Access (UDMA) and CFast cards are two kinds of super-fast CF cards. Additionally, the future of CF cards is in the hands of XQD Cards, which are smaller and have a much higher transfer speed and storage exceeding two terabytes; however, their use isn't widespread yet.
Secure Digital (SD) Memory Cards
Light and thin, SD memory cards are used with the majority of dSLR cameras. These cards have sufficient storage capacity and transfer rates for most users. More capacity can be had with the Secure Digital High Capacity (SDHC) memory card and the Secure Digital Extended Capacity (SDXC) card (note: only some cameras can fit the SDXC). UHS SD cards are stunningly fast; the UHS-I cards were the first, but the UHS-II far outpace them.
Other Types of dSLR Camera Memory Cards
Most other types of dSLR memory cards are brand-specific. Although most Sony cameras take SD cards, Memory Stick cards (standard, ProDuo and ProDuo HG) are specifically designed for them (they can fit some other cameras too). Multi Media Cards (MMC) operate much like SD cards, but have a slower transfer rate.
SxS cards (SxS-1 and SxS PRO+) are proprietary cards made by Sony that have incredibly fast read speeds. P2 and Micro P2 cards are built for the Panasonic P2 camcorders and are capable of 4K (ultra high-definition) recording.
All about Storage for dSLR Memory Cards
Capacity is the most important feature. Deciding on a concrete amount of storage capacity needed is the best way to determine which card is right. Most cards span between four and 64 gigabytes of storage, though some have lots more. Data storage depends on the format (JPEG uses less than RAW) and the resolution.
Also, note that because memory cards can get corrupted or physically damaged, some folks prefer buying several with smaller storage capacities than just one large one. That way, if one fails, only a portion of the data is lost.
For Light to Medium Use
Those snapping occasional family photos or taking casual shots of scenery don't need a lot of storage. A memory card with four or eight gigabytes of storage is enough. Consider: at a 12-megapixel photo quality, it takes roughly 678 pictures to use four gigabytes of data. For those casual users who always find themselves taking photos, get 16-32 gigabytes.
For Extended and/or Professional Use
Think of purchasing either one card between 64 and 512 gigabytes or multiple cards that add up to a desired storage level. Those recording video or shooting bursts of images are advised to go with higher storage capacities.
All About Speed for dSLR Memory Cards
Casual users don't need to spend the extra money on speed and memory; something around 30 to 60 megabytes per second will work. However, those working with high resolution images, using continuous shooting mode, filming high-definition video and doing other tasks that require a quick transfer of data absolutely need to be concerned with speed. A memory card that's too slow can cause disruptions and issues with shooting. Get one near 90 megabytes (or more) per second.
There are two types of speed for memory cards. Read speed refers to how fast data is transferred externally, for example to a computer. Write speed refers to how fast data is transferred to the card post-shot, which is very important. Some cards clearly list -- in megabytes per second -- how fast the card is. Others use an "X" notation, with X equalling 150 kilobytes; hence, a card with a speed of 400X, for instance, has a speed of 60 megabytes per second. SD cards have a class rating system; the higher the class, the faster (more megabytes-per-second) the card is.