Continuous Photo Speed and Buffer

The Faster the Better, When it Comes to Action Photos

Die-hard action photographers need digital SLR cameras with a high continuous photo speed and buffer.

This is because they know that a fraction of a second is the difference from a pretty good photo and one that is downright exceptional.

When you're dealing with fractions of a second, you need a camera that is blazing fast.

The two key indicators of the speed of a digital SLR camera are its continuous photo speed and buffer.

Continuous Photo Speed

Every digital SLR camera has a mode where you can take rapid consecutive photos.

All you have to do is hold down the camera's shutter release button, and the camera will keep snapping the photos off one by one.

Continuous photo speed is a measurement of the number of photos a camera can take in one second.

The photo speed measurement is called frames per second (fps), which pretty much means the same thing as photos per second.

This measurement makes it easy to tell if one camera is faster than another: for example, if one camera has a speed of 3fps while another has a speed of 5fps, the 5fps camera can take more consecutive photos in less time.

Here are some digital SLR cameras and their respective continuous photos speeds:

Camera	Speed (fps)
Nikon D2H	8
Canon 30D	5
Sony DSLR-A100	3

Maxxing Out the Buffer

The second half of the continuous photo speed and buffer coin is buffer.

While this may sound a lot like something that you do to your car to make it shine, in reality buffer is the number of continuous shots a digital SLR camera can store before it slows down.

Here's the rationale: every time you take a photo with your digital SLR, it has to do some processing - it can't just instantly store the photo on the memory card.

While the camera is processing the photo (before it saves to to the card) it stores the image in a temporary memory space called a buffer.

The larger the buffer, the more images the camera can store in temporary memory.

Once the buffer fills up, the camera slows down, and can no longer take photos at its maximum fps rating. For example, a 5fps camera may slow down to 2fps once the buffer fills up.

Since this is the case, modern digital SLRs all have large buffers to ensure that the camera never slows down.

Camera	Buffer Size
Nikon D2H	40
Canon 30D	30
Sony DSLR-A100	Unlimited *

* The Sony A100 lets you keep taking photos at 3fps until the memory card fills up, so it has NO buffer limit.

More Speed = More Money

Before you get excited about the possibilities of a camera that can take photos at 5fps with a buffer of 100 images, make sure that you're going to use it.

I say this because to get a camera this fast, you will pay a significant premium.

The jump from 3fps to 5fps will cost you about $1,000. While a 5fps camera also includes many other advanced features that justify the price, a principal reason to get a camera this fast is for action photography.

If all you take is portraits then being able to take 5 photos per second of your stationary subject is a bit ridiculous.

If - on the other hand - you enjoy taking snapshots at NASCAR and Formula One races, then a 5fps speed is fully justified.

Just keep in mind that while a blazing-fast camera may seem awfully tempting, you have to be prepared to pay the extra cost since a high continuous photo speed and buffer don't come cheap.