For sports and other specialized applications, photographers may want to take a lot of photographs very quickly.
A reasonable question is: How many frames can I take in a row with my DSLR camera?
The answer is: It depends, and you will probably have to dig a bit to find a meaningful answer in your camera literature or online info.
The first factor is Continuous Shooting Speed/Maximum Shooting Speed. Each camera has at least a couple Drive Modes: Single and Continuous. I own the Canon 5D Mark III, and the technical specifications list the maximum speed at 6 frames/shots per second, or 6 fps. This is a mechanical feature. In a film camera, I push the shutter button, and the film advances so I expose 6 frames each second until the roll of film is finished. For decent sports photography, I wouldn’t want to use anything less that 5 fps. Top-level sports cameras have 12 fps or faster.
But in DSLRs, it’s not as simple as exposing film. Light hits the digital sensor, a processor interprets the data to form an image, writes it to a buffer in the camera, then transfers the data to a memory card. In most situations, those steps seem to happen instantaneously. But sports photography tests the internal functions of any camera. If I’m trying to take photos faster than my camera can process them, it will stop taking photos until it catches up.
Therefore, the second factor is the Digital Processing Speed. A new digital camera is like a new computer: its processor is faster than the old model’s. So the type of processor in my camera is essential to its performance. For reasons I don’t understand, a camera’s spec sheet rarely include its processor information. Knowing which processor I have doesn’t tell me the exact speed for taking photos, but it’s a major factor.
• Canon DIGIC: Canon’s system of processing images is called DIGIC. The best cameras in 2016 have DIGIC 6+, while older cameras have a lower number.
• Nikon EXPEED: Nikon’s similarly complex system for processing images is EXPEED. Cameras introduced in 2016 have EXPEED 5, while older cameras have a lower number.
• Pentax processing info
Another little-understood factor is buffer size. Roughly speaking, data sits temporarily in the buffer while waiting to be written to the memory card. The larger the buffer, the more files you can capture quickly while your camera is storing them properly. For my Canon 5D, the technical specs state that the Maximum Burst is 13 images if capturing RAW files in their standard test. For practical purposes, that means the buffer size is 13 RAW images. If I shoot 20 RAW images in quick succession, the camera will pause part way through while it writes the rest of the data to the memory card.
When talking about DSLRs, a Shooting Burst or Maximum Burst usually refers to the number of photos I can take before my camera pauses. But for a camera phone or other camera, a shooting burst usually just means taking several photos in a row.
Another factor is File Size. A digital camera can process a small jpeg much faster than a RAW file. Almost any DSLR built since 2010, can process medium or small jpegs without issue. This means I can set my camera’s Drive Mode to Continuous High, choose medium jpeg, and it will take photos at 6 fps until the card is full. But large images process more slowly. As stated, my Maximum Burst is 13 images if capturing RAW, but 65 images if capturing large JPEGs. For sports photography, don’t choose a file size larger than you actually need.
Yet another factor is the Memory Card speed. For sports especially, use the fastest card for your camera. It will write data faster, improving the overall processing time. See the previous post Find the Right Memory Card for Your Camera.
In conclusion, Continuous Shooting Speed is only one factor in taking photos quickly. The type of camera, file size and choice of memory cards also effect speed. Do a little digging to find out how fast your camera is, and how to make it as fast as possible while you’re on assignment.