The question is often asked, “what size memory card should I buy?”  The answer varies greatly and depends on the megapixel count of your digital camera and how many photos or videos you take at given time. Some photographers take only a couple hundred photos a year; others take that many or more in a month.

The actual number of images or minutes of video you can capture on a memory card depends on other things, too, such as camera model and the image resolution and compression settings.

The amount of colors in digital images can influence their file size. For example, the file size of a black and white image will be smaller than the same scene taken in full color.

As a general rule, the following size memory card is a recommended minimum:

• 512 MB or higher for a 5 megapixel digicam
• One GB or higher for a 6 megapixel digicam
• Two GB or higher for an 8 megapixel digicam
• Four or more GB - if you shoot a lot of video or have a camera with 10 or more megapixels. If you use Secure Digital memory cards, be sure to read about SDHD cards and their special requirements.

How many memory cards?

Many digital photographers have at least two memory cards, not only for the extra capacity but for security. If one card is lost, or if it becomes corrupted, you have an additional one on hand.

For those who shoot a lot of video with a digital camera, get the largest capacity card you can afford.  Some photographers set aside one card just for shooting video. Most digital cameras made during the last few years can take high speed cards and they are well-worth the extra cost.

Memory cards are relatively inexpensive compared to just a few years ago so get the highest capacity possible. It’s better to have extra capacity on a card than to run out of it.