Does my buffer look big in this – my camera buffer that is. The world of digital photography can be a confusing one. It is a jargon-laden medium that seems made to order for techno-nerds and computer junkies, for people – mostly men (like me) – who can talk the talk but often can’t walk the walk. We snappers love to bamboozle friends and family with tales from the world of megapixels and RAW files, with anecdotes about focal length and burst rates. However, reading between the lines it’s all just digital noise and shutter lag.

Still, today’s photographer – amateur and pro alike – needs at least a passing understanding of the technicalities of digital equipment. For better or worse we now live in a film free society, well almost at least.

When pictures were still being made on film there were a few proven formats that photographers worked with: 35mm (the most popular), medium format, large format and a small handful of others. Each format had its place in the photographic food chain. Then along came digital, and everything changed. Although film is still being used, and will continue to be used, digital has taken over, especially in the consumer market.

So what’s replaced film; how do we get those terrific holiday snaps from the camera to hanging on the kitchen wall? The one thing common to all digital cameras is the need for some kind of image storage mechanism, generally referred to as a memory card.

What is not common though is the format. Having said that, however, there is one or two that are becoming common, almost industry standard:

The Compact Flash Card (CF) is a memory card that uses Flash Memory to store data. Since flash memory is very stable and can store a large amount of information in a small area it is one of the most popular kinds of cards used by camera manufacturers. But because it is, in relative terms, physically larger than other formats it is usually only used in Digital Single Lens Reflex cameras (DSLR’s), cameras that have bigger housings than their point and shoot cousins.

Secure Digital, or SD cards, are also extremely popular with manufacturers, especially for small point and shoot cameras. SD cards also use Flash Memory, making them as stable as CF cards. However, they are about half the size of CF cards, allowing camera makers to stream line their products. Not long ago SD cards were limited in how much data they could store, but with recent improvements SD cards ranging from four gigabytes to as much as 32 gigabytes of memory are now available. These new cards are called Secure Digital High Capacity cards (SDHC) and are on the market now.

oth CF and SD cards are made by a number of different manufacturers.

The most popular are Sandisk, Lexar and Fuji. How they are priced is based on how much data they can store – the number of gigabytes – and how fast the write speed is.

Write speed is another one of those digital traps. Basically the faster the write speed of a card the quicker it will store an image once the shutter button is pressed, thus allowing the photographer to keep shooting. But there is a caveat. Write speeds are designated in a numerical way: 16x, 40x, 80x, 133x and now 300x. Sure, the average High Street camera store salesman will probably steer you towards the faster cards, but the simple truth is that unless you are using a relatively high-end DSLR all the write speed in the world will not make your pictures store faster. The speed of storage is dependent on the camera’s buffer, a holding tank for pictures that have been shot. It is the buffer that allows the camera to write the pictures to the card and still let the photographer shoot. But not all buffers are created equal. Some have a greater capacity to hold pictures – DSLR’s – while others are limited. So there is no reason to spend a lot of money on a 300x memory card when your camera can’t handle it.

To illustrate, the average point and shoot camera will be able to shoot one to three pictures before the camera needs to stop and store the images. A top end professional camera can shoot up to 110 images before it needs to store the pictures to the card.

CF and SD are not the only formats on the market. Some camera manufacturers have their own dedicated memory cards. Sony developed the Memory Stick in 1998. Since then it has gone through a number of improvements and is now used in all Sony cameras, as well as mobile phones.

There is a whole raft of memory card formats – mini-SD cards, xD-Picture cards, multi-media cards, etc – but they all perform the same task: storing data, in this case pictures. The only real thing to take note of is that different camera manufacturers use different card formats. So when purchasing a new camera make sure you know what kind of card it uses. And at the same time be sure you understand how fast the camera can write pictures to the card. There is no need to by a 300x card if the camera can’t handle it.

Like any new technology, digital photography is constantly changing. It is also becoming more popular month in month out. The combination of these two factors has significantly reduced the price of memory cards.

Not long ago a one-gigabyte card would have cost close to £200. That same card today can be had for as low as ten quid.

So the key things to remember about memory cards are: they are compact storage devices that are, simply put, the digital equivalent to film; the more gigabytes the more room for pictures; cost is usually determined by size of memory plus write speed; a fast write speed may not be a necessity (depends on camera model); there are lots of formats but probably only one that fits your camera.

Memory cards are sold everywhere now, but the best prices are still on-line: www.memorybits.co.uk; www.digitaldepot.co.uk; www.memoryforless.co.uk; www.play.com

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